Remove warnings relevant to Zephyr platform

Signed-off-by: Krisztian Szilvasi <34309983+kr-t@users.noreply.github.com>

Author: kr-t

core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/src/posix.c

@@ -2213,7 +2213,7 @@ wasmtime_ssp_poll_oneoff(wasm_exec_env_t exec_env, struct fd_table *curfds,
 
 // Temporary workaround (see PR#4377)
 #ifdef BH_PLATFORM_ZEPHYR
-                    os_file_handle tfd = fos[i]->file_handle->fd;
+                    int tfd = fos[i]->file_handle->fd;
 #else
                     os_file_handle tfd = fos[i]->file_handle;
 #endif

core/shared/platform/zephyr/platform_internal.h

@@ -290,7 +290,9 @@ typedef struct timespec os_timespec;
 #define CLOCK_REALTIME 1
 #endif
 
+#ifndef CLOCK_MONOTONIC
 #define CLOCK_MONOTONIC 4
+#endif
 
 static inline int
 os_sched_yield(void)

core/shared/platform/zephyr/zephyr_file.c

@@ -6,6 +6,7 @@
 #include "platform_api_vmcore.h"
 #include "platform_api_extension.h"
 #include "libc_errno.h"
+#include "bh_common.h"
 
 #include <string.h>
 #include <stdlib.h>
@@ -1195,4 +1196,4 @@ bool
 os_is_stderr_handle(os_file_handle handle)
 {
     return (handle == (os_file_handle)stderr);
-}
+}