gdbserver: misc fixes (#214909 c 77)
Fix some tests on ppc-debian6,s390x + handled Nick Nethercote, Josef
Weidendorfer comments

* improved testing & related doc
  - added option --vex-iropt-precise-memory-exns=yes to mcsig(no)pass.vgtest
    + updated manual-core.xml
  - cleanup some comments in *.vgtest 
  - modified filter_gdb and filter_memcheck_monitor to
    handle specific ppc/debian6.0 mcsig(no)pass output
    handle specific s390x 'missing debug info'
  - added more information in README_DEVELOPPERS on how to
    investigate failing gdbserver tests.

* handled Nick Nethercote comment:
  Replaced kludgy ms.snapshot detailed
              by  ms.detailed_snaphot
  Updated documentation and test.

* handled Josef Weindendorfer comments:
   - do not report an error if ptrace_scope file can't be read.
     Instead, a debug trace is done if -d (debug) option given
   - added an option -l to give the list of active Valgrind
     gdbserver. Useful a.o. to support callgrind_control.
     Updated documentation
   - added ref. to  vgdb help in the vgdb --help message

(Philippe Waroquiers, philippe.waroquiers@skynet.be)



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@11770 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/gdbserver_tests/mcinfcallWSRU.vgtest b/gdbserver_tests/mcinfcallWSRU.vgtest
index 1b19cc7..0bb4b6a 100644
--- a/gdbserver_tests/mcinfcallWSRU.vgtest
+++ b/gdbserver_tests/mcinfcallWSRU.vgtest
@@ -7,7 +7,7 @@
 vgopts: --tool=memcheck --vgdb=yes --vgdb-error=0 --vgdb-prefix=./vgdb-prefix-mcinfcallWSRU
 # Disable on Darwin: inferior call rejected as it cannot find malloc.
 prereq: test -e gdb && ../tests/os_test linux
-# filter_gdb to replace pid and Thread numbers.
+# filter_gdb to replace pid and Thread numbers in the output of the program:
 stderr_filter: filter_gdb
 progB: gdb
 argsB:  --quiet -l 60 --nx 1>&2 ./sleepers