Add some ATF tests for libproc.

Differential Revision:	D710
Reviewed by:	jmmv, ngie, rpaulo


git-svn-id: svn+ssh://svn.freebsd.org/base/head@271937 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Ignore a test program which doesn't compile at the moment. It will be
addresed properly when integrating the DTrace tests with Kyua.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@271938 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f