cyclic: Use schedule() instead of WATCHDOG_RESET()

Globally replace all occurances of WATCHDOG_RESET() with schedule(),
which handles the HW_WATCHDOG functionality and the cyclic
infrastructure.

Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Tom Rini <trini@konsulko.com> [am335x_evm, mx6cuboxi, rpi_3,dra7xx_evm, pine64_plus, am65x_evm, j721e_evm]
diff --git a/lib/md5.c b/lib/md5.c
index 9d34465..1636ab9 100644
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -304,7 +304,7 @@
 			chunk = chunk_sz;
 		MD5Update(&context, curr, chunk);
 		curr += chunk;
-		WATCHDOG_RESET ();
+		schedule();
 	}
 #else
 	MD5Update(&context, input, len);