compositor: report .so path when load_module() fails

I want to know which module is failing to load with unresolved symbols.

Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>

src/compositor.c

@@ -2608,14 +2608,15 @@ load_module(const char *name, const char *entrypoint, void **handle)
 	module = dlopen(path, RTLD_LAZY);
 	if (!module) {
 		fprintf(stderr,
-			"failed to load module: %s\n", dlerror());
+			"failed to load module '%s': %s\n", path, dlerror());
 		return NULL;
 	}
 
 	init = dlsym(module, entrypoint);
 	if (!init) {
 		fprintf(stderr,
-			"failed to lookup init function: %s\n", dlerror());
+			"failed to lookup init function in '%s': %s\n",
+			path, dlerror());
 		return NULL;
 	}