[PATCH] New options for asan-symbolizer script: set cross-compile prefix, set path to sysroot, print help message

[Maria Guseva]

================
Comment at: lib/asan/scripts/asan_symbolize.py:417
@@ +416,3 @@
+  -s path_to_sysroot            Path to sysroot for sanitized binaries
+  -d, --demangle                Demangle function names
+Example:
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Alexander Potapenko wrote:
> Please fix the usage to reflect the newly added options.
The usage() function is unneeded now, I missed to remove it . Usage message is automatically constructed in argparse. This function must be removed.

http://reviews.llvm.org/D4703