portcullis package: remove -m64 on aarch64. (#11905)

GCC on aarch64 dose not support -m64. This patch removes the -m64
flag if target is aarch64.

var/spack/repos/builtin/packages/portcullis/package.py

@@ -45,6 +45,11 @@ def patch(self):
             'scripts/Makefile.am', string=True
         )
 
+        # remove -m64 on aarch64
+        if self.spec.satisfies('target=aarch64'):
+            for f in ['lib/Makefile.am', 'src/Makefile.am']:
+                filter_file('-m64', '', f)
+
     def build(self, spec, prefix):
         # build manpages
         make('man')