Merge pull request libgit2#4356 from pks-t/pks/static-clar

cmake: use static dependencies when building static libgit2

Author: ethomson

CMakeLists.txt

@@ -225,6 +225,10 @@ IF (MSVC)
 	SET(CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO}")
 	SET(CMAKE_SHARED_LINKER_FLAGS_MINSIZEREL "${CMAKE_EXE_LINKER_FLAGS_MINSIZEREL}")
 ELSE ()
+	IF (NOT BUILD_SHARED_LIBS)
+		SET(CMAKE_FIND_LIBRARY_SUFFIXES ".a")
+	ENDIF()
+
 	IF (ENABLE_REPRODUCIBLE_BUILDS)
 		SET(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> Dqc <TARGET> <LINK_FLAGS> <OBJECTS>")
 		SET(CMAKE_C_ARCHIVE_APPEND "<CMAKE_AR> Dq  <TARGET> <LINK_FLAGS> <OBJECTS>")