dm: sysreset: Add a Kconfig option for the 'reset' command

sysreset uclass driver provides an implementation of 'reset'
command using the sysreset_ APIs unconditionally. It also
supports the 'poweroff' command using the sysreset_ APIs,
but under a Kconfig option CONFIG_SYSRESET_CMD_POWEROFF.

Let's do the same for the 'reset' command, by introducing a
new Kconfig option CONFIG_SYSRESET_CMD_RESET, and set it to
on by default, to allow a board that don't have a sysreset
reset driver yet, but have a sysreset poweroff driver to
compile without any issue.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/drivers/sysreset/sysreset-uclass.c b/drivers/sysreset/sysreset-uclass.c
index a9908eb..6c9dc7a 100644
--- a/drivers/sysreset/sysreset-uclass.c
+++ b/drivers/sysreset/sysreset-uclass.c
@@ -119,6 +119,7 @@
 }
 
 
+#if IS_ENABLED(CONFIG_SYSRESET_CMD_RESET)
 int do_reset(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 {
 	printf("resetting ...\n");
@@ -128,6 +129,7 @@
 
 	return 0;
 }
+#endif
 
 #if IS_ENABLED(CONFIG_SYSRESET_CMD_POWEROFF)
 int do_poweroff(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])