Fix GH-8059 use $PHP_EXECUTABLE when $PHP not set

Author: remicollet

build/Makefile.global

@@ -148,6 +148,9 @@ prof-use:
 		if test ! -z "$(PHP)"; then \
 			echo Parse $< to generate $@;\
 			$(PHP) $(top_srcdir)/build/gen_stub.php $<; \
+		elif test ! -z "$(PHP_EXECUTABLE)" && test -x "$(PHP_EXECUTABLE)"; then \
+			echo Parse $< to generate $@;\
+			$(PHP_EXECUTABLE) $(top_srcdir)/build/gen_stub.php $<; \
 		fi; \
 	fi;