[testsuite, obvious] Fix paste-o in examine-backward.exp

[Sandra Loosemore]

I've checked in the attached patch to fix a clear cut-and-paste error in 
gdb.base/examine-backward.exp due to a change in a previous commit.  The 
testcase used to have the correct regexp before that, and I've verified 
this fix works by testing on nios2-elf.

-Sandra
-------------- next part --------------
A non-text attachment was scrubbed...
Name: examine-backward.patch
Type: text/x-patch
Size: 1862 bytes
Desc: not available
URL: <http://sourceware.org/pipermail/gdb-patches/attachments/20190816/685dc936/attachment.bin>