LinuxBoot/Makefile: Add check if initramfs needs to be built

initramfs is built always, ignoring CONFIG_LINUXBOOT_BUILD_INITRAMFS

Built initramfs only is CONFIG_LINUXBOOT_BUILD_INITRAMFS is set

BUG = N/A
TEST = Built and boot facebook monolith

Change-Id: I0d575ff7528fceb06b5394642527713bb071c8b3
Signed-off-by: Frans Hendriks <fhendriks@eltan.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77607
Reviewed-by: Martin L Roth <gaumless@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/payloads/external/LinuxBoot/Makefile b/payloads/external/LinuxBoot/Makefile
index 397ffdc..29339f14 100644
--- a/payloads/external/LinuxBoot/Makefile
+++ b/payloads/external/LinuxBoot/Makefile
@@ -21,7 +21,11 @@
 include targets/u-root.mk
 endif
 
+ifeq ($(CONFIG_LINUXBOOT_BUILD_INITRAMFS),y)
 build/initramfs: $(CONFIG_LINUXBOOT_INITRAMFS_PATH) | build
+else
+build/initramfs:
+endif
 ifeq ($(CONFIG_LINUXBOOT_INITRAMFS_COMPRESSION_XZ),y)
 	xz --keep --force --check=crc32 --lzma2=dict=1MiB $(CONFIG_LINUXBOOT_INITRAMFS_PATH)
 endif