Simplify cmake checks related to libosmocore
diff --git a/CMakeLists.txt b/CMakeLists.txt
index bfbfe1a..16625f2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -155,13 +155,13 @@
 if(NOT CPPUNIT_FOUND)
     message(FATAL_ERROR "CppUnit required to compile gr-gsm")
 endif()
+
+if(NOT LIBOSMOCORE_FOUND OR NOT LIBOSMOCODEC_FOUND OR NOT LIBOSMOGSM_FOUND)
+    set(LOCAL_OSMOCOM ON)
+endif()
+
 if(LOCAL_OSMOCOM)
     message(STATUS "Compiling with local osmocom libraries")
-    unset(LIBOSMOCORE_FOUND)
-    unset(LIBOSMOCODEC_FOUND)
-    unset(LIBOSMOCODING_FOUND)
-elseif(NOT LIBOSMOCORE_FOUND OR NOT LIBOSMOCODEC_FOUND)
-    message(STATUS "Compiling local version of libosmocore")
 elseif(NOT LIBOSMOCODING_FOUND)
     message(STATUS "Compiling local version of libosmocoding")
 endif()