ld: Initialize no_lto variable in LTO tests

no_lto must be initialized in lto.exp as lto_fat and lto_no_fat.
Otherwise, the testsuite will fail in some cases because of using
of an undefined variable.

ld/

        * testsuite/ld-plugin/lto.exp: Initialize no_lto variable.

Signed-off-by: Yuriy Kolerov <[email protected]>

Author: kolerov

ld/testsuite/ld-plugin/lto.exp

@@ -45,6 +45,7 @@ proc restore_notify { } {
 
 set lto_fat ""
 set lto_no_fat ""
+set no_lto ""
 if { [check_lto_fat_available] } {
   set lto_fat "-ffat-lto-objects"
   set lto_no_fat "-fno-fat-lto-objects"