Use malloc_usable_size() on any OS based on GNU libc

malloc_usable_size() is a GNU extension in GNU libc; hence, use it
every time GNU libc is used, rather than only on Linux.

Cherry-pick of bellard/quickjs@3489493.

Author: pinotree

cutils.h

@@ -43,7 +43,7 @@ extern "C" {
 #endif
 #if defined(__APPLE__)
 #include <malloc/malloc.h>
-#elif defined(__linux__) || defined(__ANDROID__) || defined(__CYGWIN__)
+#elif defined(__linux__) || defined(__ANDROID__) || defined(__CYGWIN__) || defined(__GLIBC__)
 #include <malloc.h>
 #elif defined(__FreeBSD__)
 #include <malloc_np.h>
@@ -586,7 +586,7 @@ static inline size_t js__malloc_usable_size(const void *ptr)
     return malloc_size(ptr);
 #elif defined(_WIN32)
     return _msize((void *)ptr);
-#elif defined(__linux__) || defined(__ANDROID__) || defined(__CYGWIN__) || defined(__FreeBSD__)
+#elif defined(__linux__) || defined(__ANDROID__) || defined(__CYGWIN__) || defined(__FreeBSD__) || defined(__GLIBC__)
     return malloc_usable_size((void *)ptr);
 #else
     return 0;