Description of problem:
libXcomposite-devel should require xorg-x11-proto-devel, libXfixes-devel and
libXext-devel.

Version-Release number of selected component (if applicable):
libXcomposite-devel-0.2.2.2-2.2

How reproducible:
[y4kk0@X ~]$ pkg-config --libs xcomposite
Package xproto was not found in the pkg-config search path.
Perhaps you should add the directory containing `xproto.pc'
to the PKG_CONFIG_PATH environment variable
Package 'xproto', required by 'Xcomposite', not found

(after installing xorg-x11-proto-devel)
[y4kk0@X ~]$ pkg-config --libs xcomposite
Package xfixes was not found in the pkg-config search path.
Perhaps you should add the directory containing `xfixes.pc'
to the PKG_CONFIG_PATH environment variable
Package 'xfixes', required by 'Xcomposite', not found

(after installing libXfixes-devel)
[y4kk0@X ~]$ pkg-config --libs xcomposite
Package xext was not found in the pkg-config search path.
Perhaps you should add the directory containing `xext.pc'
to the PKG_CONFIG_PATH environment variable
Package 'xext', required by 'Xcomposite', not found

(after installing libXext-devel)
[y4kk0@X ~]$ pkg-config --libs xcomposite
-lXcomposite -lXfixes
[y4kk0@X ~]$ cat /usr/lib/pkgconfig/xcomposite.pc
prefix=/usr
exec_prefix=/usr
libdir=/usr/lib
includedir=/usr/include

Name: Xcomposite
Description: X Composite  Library
Version: 0.2.2.2
Requires: xproto compositeproto >= 0.2 xfixes
Requires.private: x11 xfixes xext
Cflags: -I${includedir}
Libs: -L${libdir} -lXcomposite
[y4kk0@X ~]$