libdw: Robustify eh_frame_hdr and encoded-values reading.

Sanity check and keep track of binary_search_table data buffer length.
Add bounds check to encoded value reading. Also fix a bug when reading
the eh_frame header data from an other endian ELF image. Add a testcase
that would fail the new sanity checks because of the endian bug.

Signed-off-by: Mark Wielaard <mjw@redhat.com>
diff --git a/tests/ChangeLog b/tests/ChangeLog
index 365d98d..c05e807 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2015-01-07  Mark Wielaard  <mjw@redhat.com>
+
+	* run-addrcfi.sh: Add test for ppc32 eh_frame_hdr address search.
+
 2015-01-14  Mark Wielaard  <mjw@redhat.com>
 
 	* testfile-debug-types.bz2: New testfile.