[Minor] Try to fix link issues

contrib/aho-corasick/CMakeLists.txt

@@ -4,6 +4,7 @@ SET(AHOCORASICSRC	acism_create.c
 IF(NOT GPL_RSPAMD_BINARY)
 	ADD_LIBRARY(rspamd-actrie SHARED ${AHOCORASICSRC})
 	target_link_libraries(rspamd-actrie glib-2.0)
+	target_link_libraries(rspamd-actrie "${RSPAMD_REQUIRED_LIBRARIES}")
 
 	INSTALL(TARGETS rspamd-actrie
 			LIBRARY DESTINATION ${RSPAMD_LIBDIR})

contrib/kann/CMakeLists.txt

@@ -6,6 +6,8 @@ ELSE()
 	ADD_LIBRARY(rspamd-kann SHARED ${LIBKANNSRC})
 ENDIF()
 
+target_link_libraries(rspamd-kann "${RSPAMD_REQUIRED_LIBRARIES}")
+target_link_libraries(rspamd-kann "m")
 IF(WITH_BLAS)
     MESSAGE(STATUS "Use openblas to accelerate kann")
     TARGET_LINK_LIBRARIES(rspamd-kann ${BLAS_REQUIRED_LIBRARIES})

contrib/libev/CMakeLists.txt

@@ -63,6 +63,7 @@ IF(ENABLE_STATIC MATCHES "ON")
 ELSE()
 	ADD_LIBRARY(rspamd-ev SHARED ${LIBEVSRC})
 ENDIF()
+target_link_libraries(rspamd-ev "${RSPAMD_REQUIRED_LIBRARIES}")
 include_directories("${CMAKE_CURRENT_BINARY_DIR}")
 ADD_DEFINITIONS("-DEV_CONFIG_H=\"libev-config.h\""
 		-DEV_MULTIPLICITY=1