android,build: dont set a certain cflag globally

This fixes "msign-return-address=all" unrecognized by g++ for obj.host
Basically copied from nodejs/node#45756

Author: staltz

configure.py

@@ -1293,7 +1293,8 @@ def configure_node(o):
 
   # Enable branch protection for arm64
   if target_arch == 'arm64':
-    o['cflags']+=['-msign-return-address=all']
+    # nodejs-mobile patch: from https://github.com/nodejs/node/pull/45756
+    # o['cflags']+=['-msign-return-address=all']
     o['variables']['arm_fpu'] = options.arm_fpu or 'neon'
 
   if options.node_snapshot_main is not None:

node.gyp

@@ -113,6 +113,10 @@
     },
 
     'conditions': [
+      # nodejs-mobile patch: from https://github.com/nodejs/node/pull/45756
+      ['target_arch=="arm64"', {
+        'cflags': ['-msign-return-address=all'],  # Pointer authentication.
+      }],
       ['OS in "aix os400"', {
         'ldflags': [
           '-Wl,-bnoerrmsg',