Build system simplification/standardisation

This change makes kexec-tools work more like a standard configure-make-
make-install-type project:

* Remove $(OBJDIR) stuff. To do an out-of-tree build, just configure
from a different directory.

* Use the implicit Makefile rules more, and just edit the compiler
flags for specific targets.

* Simplify compiler/linker flags - no need for EXTRA_*

* Add TARGET_CC, and improve checks for BUILD_CC too.

* Set arch-specific flags in arch-specific makefiles, not conditional
on $(ARCH).

* Generate dependency files in the main compile, rather than as a
separate step.

* Don't #include sha256.c, but re-build it into the purgatory.

Still a work-in-progress.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 2 insertions, 0 deletions

diff --git a/purgatory/include/string.h b/purgatory/include/string.h
index 87cc4e1..14e172d 100644
--- a/purgatory/include/string.h
+++ b/purgatory/include/string.h
@@ -1,6 +1,8 @@
 #ifndef STRING_H
 #define STRING_H
 
+#include <stddef.h>
+
 size_t strnlen(const char *s, size_t max);
 void* memset(void* s, int c, size_t n);
 void* memcpy(void *dest, const void *src, size_t len);