scripts/gdb: If not building expat for gdb, disable

--with-expat=yes is unconditionally passed to the gdb configure
stage, instead of respecting the ${do_expat} decision.

Disable if not needed. Prevents error building canadian cross;

configure: error: expat is missing or unusable

Where configure stage fails to find expat on the host compiler.

Signed-off-by: "David Holsgrove" <david.holsgrove@xilinx.com>
Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
Message-Id: <4c4410a2a8aab24a29c5.1349244128@localhost.localdomain>
PatchWork-Id: 188711

 diff -durN glibc-cvs-2.9.orig/misc/syslog.c glibc-cvs-2.9/misc/syslog.c

 --- glibc-cvs-2.9.orig/misc/syslog.c	2009-06-01 10:16:50.000000000 +0200

 +++ glibc-cvs-2.9/misc/syslog.c	2009-06-01 10:17:20.000000000 +0200

 @@ -152,7 +152,7 @@

  #define	INTERNALLOG	LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID

  	/* Check for invalid bits. */

  	if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) {

 -		syslog(INTERNALLOG,

 +		__syslog(INTERNALLOG,

  		    "syslog: unknown facility/priority: %x", pri);

  		pri &= LOG_PRIMASK|LOG_FACMASK;

  	}