crypto: GnuPG based MPI lib - make files (part 3)

Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.

This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.

Due to patch size limitation, the patch is divided into 4 parts.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
diff --git a/lib/Makefile b/lib/Makefile
index a4da283..6ba8cbf 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -115,6 +115,8 @@
 
 obj-$(CONFIG_CORDIC) += cordic.o
 
+obj-$(CONFIG_MPILIB) += mpi/
+
 hostprogs-y	:= gen_crc32table
 clean-files	:= crc32table.h