Patch 4 in a revised series of cleanup patches from Will Schmidt

Add a suppression to handle a "Jump to the invalid address..." message
that gets generated on power.  This is a variation of the existing
suppressions.

While here, I also updated the "prog:" line in the vgtest file to reference
the supp_unknown executable, versus the badjump executable.  They share the
same source code, so I think this is effectively cosmetic.
 
This patch fixes Vagrind bugzilla 347686


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15233

memcheck/tests/supp_unknown.supp

@@ -13,3 +13,10 @@
    fun:main
 }
 
+{
+   <insert_a_suppression_name_here>
+   Memcheck:Jump
+   obj:*
+   fun:generic_start_main.isra.0
+   fun:(below main)
+}

memcheck/tests/supp_unknown.vgtest

@@ -1,4 +1,4 @@
 vgopts: -q --suppressions=supp_unknown.supp
-prog: badjump
+prog: supp_unknown
 cleanup: rm -f vgcore.*
 stderr_filter_args: badjump.c