removed remaining lzma references

.gitmodules

-[submodule "gxrio"]
-	path = gxrio
-	url = https://github.com/mhekkel/gxrio.git

cmake/cifppConfig.cmake.in

@@ -4,7 +4,6 @@ include(CMakeFindDependencyMacro)
 find_dependency(Threads)
 
 find_dependency(ZLIB REQUIRED)
-find_dependency(LibLZMA REQUIRED)
 
 INCLUDE("${CMAKE_CURRENT_LIST_DIR}/cifppTargets.cmake")
 

libcifpp.pc.in

@@ -8,6 +8,6 @@ Name: libcifpp
 Description: C++ library for the manipulation of mmCIF files.
 Version: @PACKAGE_VERSION@
 
-Requires.private: zlib, liblzma
+Requires.private: zlib
 Libs: -L${libdir} -lcifpp
 Cflags: -I${includedir} -pthread