flashrom: switch to building with meson

Added patches to fix meson compilation.

Reworked flashrom.mk to work with meson.

Several minor Makefile cleanups.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

utils/flashrom/patches/020-raw-access.patch

@@ -0,0 +1,10 @@
+--- a/meson.build
++++ b/meson.build
+@@ -263,6 +263,7 @@ endif
+ if config_satasii
+   srcs += 'satasii.c'
+   cargs += '-DCONFIG_SATASII=1'
++  need_raw_access = true
+ endif
+ if config_serprog
+   srcs += 'serprog.c'