kbuild: consistently decide when to rebuild a target
Consistently decide when to rebuild a target across all of
if_changed, if_changed_dep, if_changed_rule.
PHONY targets are now treated alike (ignored) for all targets
While add it make Kbuild.include almost readable by factoring out a few
bits to some common variables and reuse this in Makefile.build.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/usr/Makefile b/usr/Makefile
index 5b31c0b..e338e7b 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -3,6 +3,8 @@
#
klibcdirs:;
+PHONY += klibcdirs
+
# Generate builtin.o based on initramfs_data.o
obj-y := initramfs_data.o