unix: simplify configure nerfs during cross-compiling

All the override values here were the same for all triples. And forcing
CROSS_COMPILING in more scenarios in recent commits appears to have
tickled an issue on musl libc. So let's make the configs universal.

AFAICT the risk with the /dev/pt* checks is minimal, as Python's
`os.openpty()` should use a function from `pty.h` and not rely on
the device handles. But there is a risk we're doing something subtly
wrong.

TBH I'm not sure why device presence is a configure time check. I
would think this is the type of thing that should be a run-time
check since different environments have different devices. So I
suspect there's a CPython portability bug lingering in here...

Author: indygreg

cpython-unix/build-cpython.sh

@@ -797,60 +797,10 @@ if [ -n "${CROSS_COMPILING}" ]; then
     # configure doesn't like a handful of scenarios when cross-compiling.
     #
     # getaddrinfo buggy test fails for some reason. So we short-circuit it.
-    #
+    CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
     # The /dev/* check also fails for some reason.
-    case "${TARGET_TRIPLE}" in
-        *-apple-*)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        i686-unknown-linux-gnu)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        aarch64-unknown-linux-gnu)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        armv7-unknown-linux-gnueabi)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        armv7-unknown-linux-gnueabihf)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        mips-unknown-linux-gnu)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        mipsel-unknown-linux-gnu)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        mips64el-unknown-linux-gnuabi64)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        s390x-unknown-linux-gnu)
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_buggy_getaddrinfo=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
-            CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
-            ;;
-        x86_64-unknown-linux-musl)
-            ;;
-        *)
-            echo "unhandled cross-compiling triple; may run into issues"
-            ;;
-    esac
+    CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptc=no"
+    CONFIGURE_FLAGS="${CONFIGURE_FLAGS} ac_cv_file__dev_ptmx=no"
 fi
 
 CFLAGS=$CFLAGS CPPFLAGS=$CFLAGS LDFLAGS=$LDFLAGS \