configure: add '-uninstalled' to uninstalled .pc files

configure: add '-uninstalled' to uninstalled .pc files

pkg-config(1) expects uninstalled pc files to follow the
blah-uninstalled.pc naming convention and the behavior
of the program is impacted by it. Without this fix
overriding PKGP_CONFIG_LIBDIR is required to ensure
uninstalled files are preferred (overkill), instead of
just adding pc-uninstalled/ to the utility's search path
by setting PKG_CONFIG_PATH accordingly.

Signed-off-by: Reynaldo H. Verdejo Pinochet <reynaldo@osg.samsung.com>