gnucash master: Replace clang check with ax_check_compile_flags for -Wno-deprecated-register

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/859866ad (commit)
	from  https://github.com/Gnucash/gnucash/commit/97618e00 (commit)



commit 859866ad282c17c5c7babad5b571b9d0ebc15b38
Author: John Ralls <jralls at ceridwen.us>
Date:   Wed Jul 2 11:20:28 2014 +0200

    Replace clang check with ax_check_compile_flags for -Wno-deprecated-register



Summary of changes:
 configure.ac                       | 10 +++---
 macros/m4_ax_check_compile_flag.m4 | 74 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 79 insertions(+), 5 deletions(-)
 create mode 100644 macros/m4_ax_check_compile_flag.m4