ARCMWDT: Fix cbprintf issue with omitted function prototype

MWDT requires function to be declared with argument types.
This PR provides explisitly type cast for out routine
inside z_cbvprintf_impl().

This fixes zephyrproject-rtos#74562

Signed-off-by: Nikolay Agishev <[email protected]>

lib/os/cbprintf_complete.c

@@ -1315,13 +1315,19 @@ static inline void store_count(const struct conversion *conv,
 	}
 }
 
+/* Create local type to make calng-based compilers happy when handles OUTC() macro
+ * (see below). With strict rules (Wincompatible-function-pointer-types-strict)
+ * it's prohibited to pass arguments with mismatched types. */
+typedef int (*cbprintf_cb_local)(int c, void *ctx);
+
 /* Outline function to emit all characters in [sp, ep). */
-static int outs(cbprintf_cb out,
+static int outs(cbprintf_cb __out,
 		void *ctx,
 		const char *sp,
 		const char *ep)
 {
 	size_t count = 0;
+	cbprintf_cb_local out = __out;
 
 	while ((sp < ep) || ((ep == NULL) && *sp)) {
 		int rc = out((int)*sp++, ctx);
@@ -1335,12 +1341,14 @@ static int outs(cbprintf_cb out,
 	return (int)count;
 }
 
-int z_cbvprintf_impl(cbprintf_cb out, void *ctx, const char *fp,
+int z_cbvprintf_impl(cbprintf_cb __out, void *ctx, const char *fp,
 		     va_list ap, uint32_t flags)
 {
 	char buf[CONVERTED_BUFLEN];
 	size_t count = 0;
 	sint_value_type sint;
+	cbprintf_cb_local out = __out;
+
 
 	const bool tagged_ap = (flags & Z_CBVPRINTF_PROCESS_FLAG_TAGGED_ARGS)
 			       == Z_CBVPRINTF_PROCESS_FLAG_TAGGED_ARGS;