fix: error 'unistd.h' file not found on Windows

On https://searchfox.org/mozilla-central/rev/ead020d/mozglue/baseprofiler/public/BaseProfilerUtils.h#22, it detects Windows platform by seeing  if the `XP_WIN` macro is defined, if not then assumes it's on POSIX and includes the `<unistd.h>` header to use `getpid()`.

The `mozilla/BaseProfilerUtils.h` header file is introduced to `js/Debug.h` in https://phabricator.services.mozilla.com/D221102 (https://bugzilla.mozilla.org/show_bug.cgi?id=1911021), but it would be compiled without `XP_WIN` in our building configuration

Author: Xmader

setup.sh

@@ -64,6 +64,7 @@ sed -i'' -e 's/return !IsIteratorHelpersEnabled()/return false/' ./js/src/vm/Glo
 sed -i'' -e '/MOZ_CRASH_UNSAFE_PRINTF/,/__PRETTY_FUNCTION__);/d' ./mfbt/LinkedList.h # would crash in Debug Build: in `~LinkedList()` it should have removed all this list's elements before the list's destruction
 sed -i'' -e '/MOZ_ASSERT(stackRootPtr == nullptr);/d' ./js/src/vm/JSContext.cpp # would assert false in Debug Build since we extensively use `new JS::Rooted`
 sed -i'' -e 's/"-fuse-ld=ld"/"-ld64" if c_compiler.version > "14.0.0" else "-fuse-ld=ld"/' ./build/moz.configure/toolchain.configure # XCode 15 changed the linker behaviour. See https://developer.apple.com/documentation/xcode-release-notes/xcode-15-release-notes#Linking
+sed -i'' -e 's/defined(XP_WIN)/defined(_WIN32)/' ./mozglue/baseprofiler/public/BaseProfilerUtils.h # this header file is introduced to js/Debug.h in https://phabricator.services.mozilla.com/D221102, but it would be compiled without XP_WIN in this building configuration
 
 cd js/src
 mkdir -p _build
@@ -81,6 +82,7 @@ mkdir -p ../../../../_spidermonkey_install/
   --disable-explicit-resource-management
 # disable-explicit-resource-management: Disable the `using` syntax that is enabled by default in SpiderMonkey nightly, otherwise the header files will disagree with the compiled lib .so file
 #                                       when it's using a `IF_EXPLICIT_RESOURCE_MANAGEMENT` macro, e.g., the `enum JSProtoKey` index would be off by 1 (header `JSProto_Uint8Array` 27 will be interpreted as `JSProto_Int8Array` in lib as lib has an extra element)
+#                                       https://bugzilla.mozilla.org/show_bug.cgi?id=1940342
 make -j$CPUS
 echo "Done building spidermonkey"