spi: Register spi_master state so spi_master_4ba() is valid

Due to a miss-match between dispatch mechanisms between forks
state wasn't getting registered for spi_master_4ba() to be
properly defined. This attempts to remedy the issue while not
introducing even more technical debt - i.e., half a step back
instead of two.

BUG=chromium:995439
TEST=none
BRANCH=none

Change-Id: Iec42cc1133fa65a17fecf03e2a9390e7c3419e69
Signed-off-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/flashrom/+/1771375
Reviewed-by: Mathew King <mathewk@chromium.org>
diff --git a/programmer.h b/programmer.h
index 64ef8ea..a6c3c7c 100644
--- a/programmer.h
+++ b/programmer.h
@@ -595,7 +595,7 @@
 int default_spi_send_multicommand(const struct flashctx *flash, struct spi_command *cmds);
 int default_spi_read(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len);
 int default_spi_write_256(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len);
-void register_spi_master(const struct spi_master *programmer);
+int register_spi_master(const struct spi_master *programmer);
 
 /* The following enum is needed by ich_descriptor_tool and ich* code as well as in chipset_enable.c. */
  enum ich_chipset {