gnucash master: Refine forcing C11 to handle case where AC_PROG_CC_C99 doesn't set -std=

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/80034b39 (commit)
	from  https://github.com/Gnucash/gnucash/commit/b9de55c8 (commit)



commit 80034b39bc3931821408705988b9d05cc47207e2
Author: John Ralls <jralls at ceridwen.us>
Date:   Mon May 25 11:06:50 2015 -0700

    Refine forcing C11 to handle case where AC_PROG_CC_C99 doesn't set -std=



Summary of changes:
 configure.ac | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)