build: use zoslib_include_dir provided by node-gyp

The path is based on the zoslib gyp path passed to configure.py
via --static-zoslib-gyp arg.

PR-URL: nodejs#41713
Co-authored-by: Gaby Baghdadi <baghdadi@ca.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

common.gypi

@@ -615,7 +615,7 @@
           '-q64',
         ],
         # for addons due to v8config.h include of "zos-base.h":
-        'include_dirs':  ['$(ZOSLIB_INCLUDES)'],
+        'include_dirs':  ['<(zoslib_include_dir)'],
       }],
     ],
   }

configure.py

@@ -1158,7 +1158,8 @@ def configure_zos(o):
   o['variables']['node_static_zoslib'] = b(True)
   if options.static_zoslib_gyp:
     # Apply to all Node.js components for now
-    o['include_dirs'] += [os.path.dirname(options.static_zoslib_gyp) + '/include']
+    o['variables']['zoslib_include_dir'] = os.path.dirname(options.static_zoslib_gyp) + '/include'
+    o['include_dirs'] += [o['variables']['zoslib_include_dir']]
   else:
     raise Exception('--static-zoslib-gyp=<path to zoslib.gyp file> is required.')