flashchips: Add missing block erasers for GD25Q256D

Change-Id: I7e49e468c7f1eaf0ddd5fc08d6cc6569274faf94
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/35798
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
diff --git a/flashchips.c b/flashchips.c
index 65110fe..e487956 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -6290,12 +6290,21 @@
 		{
 			{
 				.eraseblocks = { {4 * 1024, 8192} },
+				.block_erase = spi_block_erase_21,
+			}, {
+				.eraseblocks = { {4 * 1024, 8192} },
 				.block_erase = spi_block_erase_20,
 			}, {
 				.eraseblocks = { {32 * 1024, 1024} },
+				.block_erase = spi_block_erase_5c,
+			}, {
+				.eraseblocks = { {32 * 1024, 1024} },
 				.block_erase = spi_block_erase_52,
 			}, {
 				.eraseblocks = { {64 * 1024, 512} },
+				.block_erase = spi_block_erase_dc,
+			}, {
+				.eraseblocks = { {64 * 1024, 512} },
 				.block_erase = spi_block_erase_d8,
 			}, {
 				.eraseblocks = { {32 * 1024 * 1024, 1} },