Obsolete pkg-config module for CMake, use FindPkgConfig instead.

This module defines the following macro:

PKGCONFIG(package includedir libdir linkflags cflags)

Calling PKGCONFIG will fill the desired information into the 4 given arguments, e.g. PKGCONFIG(libart-2.0 LIBART_INCLUDE_DIR LIBART_LINK_DIR LIBART_LINK_FLAGS LIBART_CFLAGS) if pkg-config was NOT found or the specified software package doesn’t exist, the variable will be empty when the function returns, otherwise they will contain the respective information