spi_master: Use new API to register shutdown function

This allows spi masters to register shutdown function in spi_master
struct, which means there is no need to call register_shutdown in init
function, since this call is now a part of register_spi_master.

As a consequence of using new API, two things are happening here:
1) No resource leakage anymore in case register_shutdown() would fail,
2) Fixed propagation of register_spi_master() return values.

Basic testing: when I comment out free(data) in linux_spi_shutdown, test
fails with error
../linux_spi.c:235: note: block 0x55a4db276510 allocated here
ERROR: linux_spi_init_and_shutdown_test_success leaked 1 block(s)
Means, shutdown function is invoked.

Tested:  1) builds and ninja test including CB:56911
2) On ARMv7 device
flashrom -p linux_spi -V
-> using linux_spi, chip found
3) On x86_64 AMD device
flashrom -p internal -V
-> this is actually using sb600spi, chip found

flashrom-stable: Updated `dirtyjtag_spi` which was added earlier.

Change-Id: Ib60300f9ddb295a255d5ef3f8da0e07064207140
Signed-off-by: Anastasia Klimchuk <aklm@chromium.org>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/56103
Original-Reviewed-by: Nico Huber <nico.h@gmx.de>
Original-Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Original-Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/72231
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/digilent_spi.c b/digilent_spi.c
index d39d686..128c95c 100644
--- a/digilent_spi.c
+++ b/digilent_spi.c
@@ -312,6 +312,8 @@
 	return 0;
 }
 
+static int digilent_spi_shutdown(void *data);
+
 static const struct spi_master spi_master_digilent_spi = {
 	.features	= SPI_MASTER_4BA,
 	.max_data_read	= 252,
@@ -321,6 +323,7 @@
 	.read		= default_spi_read,
 	.write_256	= default_spi_write_256,
 	.write_aai	= default_spi_write_aai,
+	.shutdown	= digilent_spi_shutdown,
 };
 
 
@@ -446,10 +449,7 @@
 	if (spi_set_mode(0x00) != 0)
 		goto close_handle;
 
-	register_shutdown(digilent_spi_shutdown, NULL);
-	register_spi_master(&spi_master_digilent_spi, NULL);
-
-	return 0;
+	return register_spi_master(&spi_master_digilent_spi, NULL);
 
 close_handle:
 	libusb_close(handle);