[core] Fix compilation warnings

arduino/libretuya/common/main.cpp

@@ -10,6 +10,10 @@ extern "C" {
 fal_partition_t fal_root_part = NULL;
 }
 
+// Arduino framework initialization.
+// May be redefined by family files.
+void init() __attribute__((weak));
+
 // Weak empty variant initialization function.
 // May be redefined by variant files.
 void initVariant() __attribute__((weak));

arduino/libretuya/libraries/Update/uf2ota/uf2priv.c

@@ -118,12 +118,12 @@ uf2_err_t uf2_update_parts(uf2_ota_t *ctx, char *part1, char *part2) {
 	ctx->erased_length = 0;
 
 	if (part1[0]) {
-		ctx->part1 = fal_partition_find(part1);
+		ctx->part1 = (fal_partition_t)fal_partition_find(part1);
 		if (!ctx->part1)
 			return UF2_ERR_PART_404;
 	}
 	if (part2[0]) {
-		ctx->part2 = fal_partition_find(part2);
+		ctx->part2 = (fal_partition_t)fal_partition_find(part2);
 		if (!ctx->part2)
 			return UF2_ERR_PART_404;
 	}

arduino/libretuya/posix/strdup.c

@@ -1,6 +1,7 @@
 /* Copyright (c) Kuba Szczodrzyński 2022-05-16. */
 
 #include <stddef.h>
+#include <sdk_mem.h>
 
 __attribute__((weak)) char *strdup(const char *s) {
 	size_t len = strlen(s) + 1;

arduino/realtek-ambz/cores/arduino/wiring.c

@@ -33,10 +33,6 @@ static __inline uint32_t __get_ipsr__(void) {
 
 void *gpio_pin_struct[PINS_COUNT] = {NULL};
 
-__attribute__((weak)) void init(void) {
-	// nop
-}
-
 void delay(uint32_t ms) {
 	/* osStatus ret; */