par_master: Fix propagation of register_par_master() return values

This patch checks return value of register_par_master()
so that in case of an error this error is not ignored anymore.

Tested: builds and ninja test

Change-Id: I377afae41708c7433a56615e2f096bce9c5349f1
Signed-off-by: Anastasia Klimchuk <aklm@chromium.org>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/57192
Original-Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Original-Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/72234
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/gfxnvidia.c b/gfxnvidia.c
index ec04a94..85d6d71 100644
--- a/gfxnvidia.c
+++ b/gfxnvidia.c
@@ -104,9 +104,7 @@
 
 	/* Write/erase doesn't work. */
 	programmer_may_write = false;
-	register_par_master(&par_master_gfxnvidia, BUS_PARALLEL, NULL);
-
-	return 0;
+	return register_par_master(&par_master_gfxnvidia, BUS_PARALLEL, NULL);
 }
 
 static void gfxnvidia_chip_writeb(const struct flashctx *flash, uint8_t val,