MIPS: allow using generic sysreset drivers

Avoid duplicating do_reset definition if SYSRESET is enabled for MIPS

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/mips/cpu/cpu.c b/arch/mips/cpu/cpu.c
index 1b919ed..55e6498 100644
--- a/arch/mips/cpu/cpu.c
+++ b/arch/mips/cpu/cpu.c
@@ -12,6 +12,7 @@
 #include <asm/mipsregs.h>
 #include <asm/reboot.h>
 
+#ifndef CONFIG_SYSRESET
 void __weak _machine_restart(void)
 {
 	fprintf(stderr, "*** reset failed ***\n");
@@ -26,6 +27,7 @@
 
 	return 0;
 }
+#endif
 
 void write_one_tlb(int index, u32 pagemask, u32 hi, u32 low0, u32 low1)
 {