Extend os_mmap to support map file from fd (#2763)

Add an extra argument `os_file_handle file` for `os_mmap` to support
mapping file from a file fd, and remove `os_get_invalid_handle` from
`posix_file.c` and `win_file.c`, instead, add it in the `platform_internal.h`
files to remove the dependency on libc-wasi.

Signed-off-by: Huang Qi <huangqi3@xiaomi.com>

core/shared/platform/riot/platform_internal.h

@@ -80,4 +80,10 @@ int isnan(double x);
 /* clang-format on */
 #endif
 
+static inline os_file_handle
+os_get_invalid_handle()
+{
+    return -1;
+}
+
 #endif /* end of _BH_PLATFORM_H */

core/shared/platform/riot/riot_platform.c

@@ -50,7 +50,7 @@ os_dumps_proc_mem_info(char *out, unsigned int size)
 }
 
 void *
-os_mmap(void *hint, size_t size, int prot, int flags)
+os_mmap(void *hint, size_t size, int prot, int flags, os_file_handle file)
 {
     if (size > ((unsigned)~0))
         return NULL;