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 cf304fc578a748439a96dccaaac39a9566c94e07..69f63b1fe698d6245834278bce9de3dd4ea7a594 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.