libressl.sh: disable ASM for ARM64 Windows [ci skip]

ASM has been enabled by default in LibreSSL 4.2.0:
libressl/portable@1df6b52
libressl/portable#1177

This caused compiler warnings, and also broke using SSL, possibly due
to using the ASM bignum implementation where the warnings are shown.

This issue is masked by llvm-mingw 21 creating broken LibreSSL
ARM64 binaries, crashing with 0xC0000409 (STATUS_STACK_BUFFER_OVERRUN).

Ref: libressl/portable#1210

Author: vszakats

libressl.sh

@@ -5,6 +5,11 @@
 
 # Caveats (as of 4.2.0):
 # - Most ASM is implemented for x64 only.
+# - ASM implemented for ARM64 on Windows triggers -Wasm-operand-widths, 2300+ times.
+#   It breaks connecting with TLS:
+#     curl: (35) TLS connect error: error:04FFF077:rsa routines:CRYPTO_internal:wrong signature length
+#   or cause a hang, depending on website.
+#   https://github.com/libressl/portable/issues/1210
 # - Not possible to hide most ASM symbols from shared lib exports in Linux, macOS.
 #   https://github.com/libressl/portable/issues/957
 #   Local patch exists for this, or ASM can be disabled.
@@ -40,6 +45,10 @@ _VER="$1"
   CFLAGS=''
   CPPFLAGS='-DOPENSSL_NO_FILENAMES'
 
+  if [ "${_OS}" = 'win' ] && [ "${_CPU}" = 'a64' ]; then
+    options+=' -DENABLE_ASM=OFF'  # Pending: https://github.com/libressl/portable/issues/1210
+  fi
+
   if [[ "${_CONFIG}" != *'debug'* ]]; then
     CPPFLAGS+=' -DNDEBUG'
   fi