[PHP] Recompile PHP with MAIN_MODULE set to 2

[mho22]

Motivation for the change, related issues

TBD

Implementation details

TBD

Testing Instructions (or ideally a Blueprint)

CI

[mho22]

Recompiling PHP with MAIN_MODULE=2 implies linking it with every shared libraries used.

Meaning :

	emcc $OPTIMIZATION_FLAGS \
	--js-library /root/phpwasm-emscripten-library.js \
	--js-library /root/phpwasm-emscripten-library-dynamic-linking.js \
	--js-library /root/phpwasm-emscripten-library-known-undefined-functions.js \
	$PLATFORM_SPECIFIC_ARGS \
	-I .  \
	-I ext   \
	-I ext/json   \
	-I Zend  \
	-I main  \
	-I TSRM/ \
	-I/root/lib -I/root/lib/include \
	-L/root/lib -L/root/lib/lib/ \
	-D__x86_64__\
	-lproxyfs.js \
	$ASYNCIFY_FLAGS \
	$(cat /root/.emcc-php-wasm-flags) \
+	/root/extensions/intl.so \
+	/root/extensions/xdebug.so \
	-s MAIN_MODULE=2 \
	-s EXPORTED_FUNCTIONS="$EXPORTED_FUNCTIONS" \

This means I will need to access node-builds and web-builds inside this Dockerfile.

Another error is related to getpid. I replaced __wrap_getpid with getpid. But this can possibly break file locking.

[mho22]

It basically moved the 4-5Mb from .wasm to .js file. Not really what I expected. But I now understand how things should work.