lib: libc: arcmwdt: add declarations for reentrant time functions

ARC MWDT library does not contain implementations for the reentrant
POSIX time functions, so common Zephyr implementations end up being
used instead. However, there are no declarations, so we just add them
here, unguarded, until a better place is found.

Signed-off-by: Ilya Tagunov <[email protected]>

Author: tagunil

lib/libc/arcmwdt/include/time.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2024 Synopsys
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef LIB_LIBC_ARCMWDT_INCLUDE_TIME_H_
+#define LIB_LIBC_ARCMWDT_INCLUDE_TIME_H_
+
+#include_next <time.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern char *asctime_r(const struct tm *tp, char *buf);
+extern char *ctime_r(const time_t *clock, char *buf);
+extern struct tm *gmtime_r(const time_t *timep, struct tm *result);
+extern struct tm *localtime_r(const time_t *timer, struct tm *result);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LIB_LIBC_ARCMWDT_INCLUDE_TIME_H_ */