PATCH: Avoid use of [string match] to test strings for equality in runtest.exp

Older versions of Tcl may have required this use of [string match], but 
modern Tcl allows the much simpler "==" operator.  According to time(n), 
"==" is also slightly faster in "if" expressions in addition to being 
more robust against "odd" inputs.  Tidying the "if {...} {return $name}; 
if {...} {return $name}" is on my local TODO list along with checking 
for similar constructions elsewhere.

(I mention history in a "please do not blame previous contributors for 
this; they probably had no choice and it was good code at the time; the 
Tcl language has greatly improved since then" sense.)

----
ChangeLog entry:
	* runtest.exp: Fix archaic use of [string match].
----
patch:
----
diff --git a/runtest.exp b/runtest.exp
index a389c53..34e22d3 100644
--- a/runtest.exp
+++ b/runtest.exp
@@ -199,16 +199,16 @@ proc transform { name } {
     global host_triplet
     global board
 
-    if {[string match $target_triplet $host_triplet]} {
+    if { $target_triplet == $host_triplet } {
 	return $name
     }
-    if {[string match "native" $target_triplet]} {
+    if { $target_triplet == "native" } {
 	return $name
     }
     if {[board_info host exists no_transform_name]} {
 	return $name
     }
-    if {[string match "" $target_triplet]} {
+    if { $target_triplet == "" } {
 	return $name
     } else {
 	if {[info exists board]} {
@@ -536,7 +536,7 @@ verbose "Verbose level is $verbose"
 #
 # get the users login name
 #
-if {[string match "" $logname]} {
+if { $logname == "" } {
     if {[info exists env(USER)]} {
 	set logname $env(USER)
     } else {
@@ -623,7 +623,7 @@ load_file [file join $base_dir $local_init_file]
 # command line.
 #
 
-if {[expr {[string match "." $objdir] || [string match $srcdir $objdir]}]} {
+if { $objdir == "." || $objdir == $srcdir } {
     set objdir $base_dir
 } else {
     load_file [file join $objdir $local_init_file]
----


-- Jacob