[mips] update stderr exp file for tc19_shadowmem

[mips] update stderr exp file for tc19_shadowmem

A few changes have had impact on expected output of tc19_shadowmem recently.
These are:
- r14175 (added extra "Block was alloc'd by thread #x" output)
- r13983 (removed "pthread_create_WRK (hg_intercepts.c:" output)
- r13965 (a few empty lines removed)

However, expected stderr file for mips32 has not been updated accordingly.
Update it now. This fixes helgrind/tests/tc19_shadowmem failure on mips32.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15832