coreboot: Replace all IS_ENABLED(CONFIG_XXX) with CONFIG(XXX)

This patch is a raw application of

 find src/ -type f | xargs sed -i -e 's/IS_ENABLED\s*(CONFIG_/CONFIG(/g'

Change-Id: I6262d6d5c23cabe23c242b4f38d446b74fe16b88
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31774
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/cpu/x86/smm/smihandler.c

@@ -19,7 +19,7 @@
 #include <cpu/x86/cache.h>
 #include <cpu/x86/smm.h>
 
-#if IS_ENABLED(CONFIG_SPI_FLASH_SMM)
+#if CONFIG(SPI_FLASH_SMM)
 #include <spi-generic.h>
 #endif
 
@@ -186,7 +186,7 @@ void smi_handler(u32 smm_revision)
 
 	/* Allow drivers to initialize variables in SMM context. */
 	if (do_driver_init) {
-#if IS_ENABLED(CONFIG_SPI_FLASH_SMM)
+#if CONFIG(SPI_FLASH_SMM)
 		spi_init();
 #endif
 		do_driver_init = 0;