oeqa/runtime/cases/multilib.py: skip if needed packages are not available
1) The test cases use 'readelf' command to do the check. This command
is from binutils. So skip the test if the needed binutils package is
not installed.
The related error message in log.do_testimage is like below.
Output: sh: readelf: not found
2) The test case tests /lib/libc.so.6 from lib32-libc6. So skip the test
if lib32-libc6 is not installed.
The related error message in log.do_testimage is like below.
Output: readelf: Error: 'lib/libc.so.6': No such file
Signed-off-by: Chen Qi <Qi.Chen@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
