This patch add SELINUX_LIBS and STATIC_LIBS variables.

This patch add SELINUX_LIBS and STATIC_LIBS variables.

For static builds dependency for SELinux libs is not handled by 'ar'.
Till better solution is found, for static builds STATIC_LIBS is used.

Patch updates SELinux detection to use 3rd & 4th parameter for Success/Fail.
Also removes detection of pthread from this check as we know which
version of libdevmapper we are going to link with lvm after merge.

SELinux header check moved to the SELinux test code.