treewide: rename GENERIC_SPD_BIN to HAVE_SPD_BIN_IN_CBFS

The name GENERIC_SPD_BIN doesn't reflect anymore what that config is
used for, so rename it to HAVE_SPD_BIN_IN_CBFS.

Change-Id: I4004c48da205949e05101039abd4cf32666787df
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45147
Reviewed-by:  Felix Singer <felixsinger@posteo.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/lib/Kconfig b/src/lib/Kconfig
index d91ec58..d6e7e51 100644
--- a/src/lib/Kconfig
+++ b/src/lib/Kconfig
@@ -30,7 +30,7 @@
 	  Selected by features that require to parse and manipulate a flattened
 	  devicetree in ramstage.
 
-config GENERIC_SPD_BIN
+config HAVE_SPD_IN_CBFS
 	bool
 	help
 	  If enabled, add support for adding spd.hex files in cbfs as spd.bin