Export ASAN_OPTIONS for the whole build

Export ASAN_OPTIONS for the whole build

Export ASAN_OPTIONS environment variable from the
gdb.spec affects all of subordinate configure scripts
where ASAN_OPTIONS environment variable is expected to be set.
Set it to content read from /ASAN_OPTIONS file if exists, empty
content otherwise.

        * packaging/gdb.spec: export ASAN_OPTIONS

Change-Id: Ib2128c6c375a6f71c574ae6c51d6a9657c5f4dc4
Signed-off-by: Yaroslav Yamshchikov <y.yamshchiko@samsung.com>
Signed-off-by: Dongkyun Son <dongkyun.s@samsung.com>