build: add dependency on libavutil for GNU/Linux

Change-Id: I3d43fd9f5782f5ebf7db9b2cef6b5d294e7aa36c

CMakeLists.txt

@@ -361,6 +361,7 @@ elseif (NOT APPLE)
   endif()
 
   pkg_check_modules(XCB xcb)
+  pkg_check_modules(LIBAVUTIL libavutil>=55.75.100)
 
   include_directories(
     ${LIBCLIENT_SRC_DIR}
@@ -368,7 +369,8 @@ elseif (NOT APPLE)
     ${LIBNOTIFY_INCLUDE_DIRS}
     ${LIBGDKPIXBUF_INCLUDE_DIRS}
     ${GLIB_INCLUDE_DIRS}
-    ${XCB_INCLUDE_DIRS})
+    ${XCB_INCLUDE_DIRS}
+    ${LIBAVUTIL_INCLUDE_DIRS})
 
   set(JAMI_DATA_PREFIX "${CMAKE_INSTALL_PREFIX}/share")
 
@@ -550,7 +552,8 @@ elseif (NOT APPLE)
     ${LIBGDKPIXBUF_LIBRARIES}
     ${GLIB_LIBRARIES}
     ${GIO_LIBRARIES}
-    ${XCB_LIBRARIES})
+    ${XCB_LIBRARIES}
+    ${LIBAVUTIL_LIBRARIES})
 
   # Installation rules
   install(