tcl: [3/3] prepare for jimtcl 0.81 'expr' syntax change

Jimtcl commit 1843b79a03dd ("expr: TIP 526, only support a single
arg") drops the support for multi-argument syntax for the TCL
command 'expr'.

Fix manually the remaining lines that don't match simple patterns
and would require dedicated boring scripting.
Remove the 'expr' command where appropriate.

Change-Id: Ia75210c8447f88d38515addab4a836af9103096d
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/6161
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

tcl/target/u8500.cfg

@@ -18,12 +18,12 @@ proc ocd_gdb_restart {target_id} {
     global _TARGETNAME_1
 	global _SMP
     targets $_TARGETNAME_1
-	if { [expr ($_SMP == 1)] } {
+	if { $_SMP == 1 } {
 	cortex_a smp off
 	}
 	rst_run
 	halt
-	if { [expr ($_SMP == 1)]} {
+	if { $_SMP == 1 } {
 	cortex_a smp on
 	}
 }