assert: Distinguish between assert and exception

CURRENT_REGS may change during assert handling, so pass
in the 'regs' parameter at the entry point of _assert.

Signed-off-by: zhangyuan21 <zhangyuan21@xiaomi.com>

libs/libc/assert/lib_assert.c

@@ -33,6 +33,6 @@
 
 void __assert(FAR const char *filename, int linenum, FAR const char *msg)
 {
-  _assert(filename, linenum, msg);
+  _assert(filename, linenum, msg, NULL);
   abort();
 }