tools/firmware/Makfile: Respect caller's CONFIG_PV_SHIM

This makes it easier to disable the shim build.  (In Debian we need to
build the shim separately because it needs different compiler flags
and a different XEN_COMPILE_ARCH.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/tools/firmware/Makefile b/tools/firmware/Makefile
index 5a7cf7766d491e5517f4e65eb14f3f836be3d6e9..d6104e6219c4dd801180e8c6c360599e30a99e8a 100644 (file)
--- a/tools/firmware/Makefile
+++ b/tools/firmware/Makefile
@@ -2,7 +2,7 @@ XEN_ROOT = $(CURDIR)/../..
 include $(XEN_ROOT)/tools/Rules.mk
 
 ifneq ($(XEN_TARGET_ARCH),x86_32)
-CONFIG_PV_SHIM := y
+CONFIG_PV_SHIM ?= y
 endif
 
 # hvmloader is a 32-bit protected mode binary.