cyrus-sasl: Avoid to call AC_TRY_RUN

If the gssapi libraries are compiled before cyrus-sasl, configure will call
AC_TRY_RUN to check if gssapi libraries support SPNEGO, but calling AC_TRY_RUN
will fail on cross-compile environment.

Signed-off-by: Roy.Li <rongqing.li@windriver.com>
Signed-off-by: Joe MacDonald <joe.macdonald@windriver.com>