Makefile: fix overriding of make command line arguments

Command line arguments given when executing make should not stop us
from setting commonly user-configurable variables like CPPFLAGS or
Without this patch 'make CPPFLAGS="-Ifail"' would fail to find
libusb1 headers and abort.
Add override statements where we append mandatory options to
these variables to make (Debian) packagers more happy.

Also, r1920 introduced some explicit calls to pkg-config instead of
$(PKG_CONFIG). This patch corrects that as well.

Corresponding to flashrom svn r1931.

Signed-off-by: Stefan Tauner <>
Acked-by: Carl-Daniel Hailfinger <>
1 file changed