e-plugin-lib.c uses symbols from gmodule but doesn't explicitely link
against gmodule, this makes building fail:

  CCLD   libevolution-module-plugin-lib.la
e-plugin-lib.c:64: error: undefined reference to 'g_module_open'
e-plugin-lib.c:68: error: undefined reference to 'g_module_error'
e-plugin-lib.c:78: error: undefined reference to 'g_module_symbol'
e-plugin-lib.c:86: error: undefined reference to 'g_module_close'
e-plugin-lib.c:105: error: undefined reference to 'g_module_symbol'
e-plugin-lib.c:224: error: undefined reference to 'g_module_close'
collect2: ld returned 1 exit status