update C/C, fix srpm build failures on fedora

krb5-config (used by FindGSSAPI) returns `-lkrb5 -lk5crypto -lcom_err`
but only libkrb5 is actually used by the gssapi plugin. The other two
result in unneeded dependencies unless they're tagged optional when
linked with --as-needed.

Some distributions use --as-needed automatically, which causes our
builds to differ from srpm builds, introducing failures in buildbot.

Let's always use --as-needed for gssapi plugin

libmariadb @ 380ee323

-Subproject commit a6665e65c05c00f9df983a0f788a643ca7bc084c
+Subproject commit 380ee32375bb36b68796c1c3eb09285f03fea5f5

plugin/auth_gssapi/CMakeLists.txt

@@ -38,6 +38,7 @@ ELSE()
    IF(HAVE_KRB5_XFREE)
      ADD_DEFINITIONS(-DHAVE_KRB5_XFREE=1)
    ENDIF()
+   MY_CHECK_AND_SET_COMPILER_FLAG(-Wl,--as-needed)
 
  ELSE()
    # Can't build plugin