Smarter libgme ldflag detection

debian/rules

@@ -71,8 +71,15 @@ MENUFILE2 = title="$(TITLE)" command="/$(PKGDIR)/$(PACKAGE)"
 export PKG_CONFIG_LIBDIR = /usr/lib/$(CROSS_COMPILE_HOST)/pkgconfig
 BINDIR :=  $(DIR)/bin/Linux/Release
 LDFLAGS += "-Wl,-rpath=/usr/lib/$(CROSS_COMPILE_HOST)"
+
 # FIXME some libgme-dev packages don't use pkg-config yet, so include the linker flag ourselves
+PKG_CONFIG?=pkg-config
+LIBGME_PKGCONFIG?=libgme
+LIBGME_LDFLAGS?=$(shell $(PKG_CONFIG) $(LIBGME_PKGCONFIG) --libs)
+
+ifeq ($(LIBGME_LDFLAGS),)
 MAKEARGS += LIBGME_LDFLAGS=-lgme
+endif
 
 build:
 	$(MKDIR) $(BINDIR)/debug