[PATCH xserver] configure: use backticks rather than $() for commands

[Gaetan Nadon]

This patch to xserver configure.ac is to increase code portability to
non POSIX system by using backticks rather than $() for command
substitution for BUILD_DATE and BUILD_TIME.

Signed-off-by: Gaetan Nadon <memsize at videotron.ca>
---
 configure.ac |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 7e2c6a5..eb92251 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2094,9 +2094,9 @@ AC_TRY_COMPILE([
 
 AC_DEFINE_DIR(PROJECTROOT, prefix, [Overall prefix])
 
-BUILD_DATE="$(date +'%Y%m%d')"
+BUILD_DATE="`date +'%Y%m%d'`"
 AC_SUBST([BUILD_DATE])
-BUILD_TIME="$(date +'1%H%M%S')"
+BUILD_TIME="`date +'1%H%M%S'`"
 AC_SUBST([BUILD_TIME])
 
 DIX_CFLAGS="-DHAVE_DIX_CONFIG_H $XSERVER_CFLAGS"
-- 
1.6.0.4

Resending with better message body for review