Portability fixes and cleanups

Move Mac OS X IOKit/DirectHW availability checks in the Makefile from
compiler check to pciutils check.

Print the compiler error messages for feature detection.

Add DOS libpci in the Makefile includes only if a PCI-based programmer
was requested.

Restrict mmap usage in ich_descriptors_tool to Unix style systems.

Build ich_descriptors_tool with the correct .exe extension on
DOS/Windows.

Build ich_descriptors_tool by default on x86. (Patch by Stefan Tauner)

Print the Windows version instead of "unknown machine" on Windows.

Don't #define our own __DARWIN__, use the standard OS X detection
method.

Update the README.

Add more generated files to svn:ignore

Corresponding to flashrom svn r1567.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
diff --git a/cbtable.c b/cbtable.c
index 4495d9d..b4fb809 100644
--- a/cbtable.c
+++ b/cbtable.c
@@ -211,7 +211,7 @@
 	struct lb_header *lb_table;
 	struct lb_record *rec, *last;
 
-#ifdef __DARWIN__
+#if defined(__MACH__) && defined(__APPLE__)
 	/* This is a hack. DirectHW fails to map physical address 0x00000000.
 	 * Why?
 	 */