[lld] Fix test failure from d978656

Tweak the test to account for the slightly different wording of the
error message.

lld/test/ELF/undef.s

@@ -52,7 +52,7 @@
 # is requested, even if that particular part of the line information is not currently required.
 # Also show that the warnings are only printed once.
 # CHECK:      warning: parsing line table prologue at 0x00000000 should have ended at 0x00000038 but it ended at 0x00000037
-# CHECK-NEXT: warning: parsing line table prologue at offset 0x0000005b found unsupported version 1
+# CHECK-NEXT: warning: parsing line table prologue at offset 0x0000005b: unsupported version 1
 # CHECK-NEXT: warning: last sequence in debug line table at offset 0x00000061 is not terminated
 # CHECK:      error: undefined symbol: zed6a
 # CHECK-NEXT: >>> referenced by undef-bad-debug.s:11 (dir{{/|\\}}undef-bad-debug.s:11)