File readable check by ::fopen instead of ::access

File readable check by ::fopen instead of ::access

To adjust CAP_DAC_READ_SEARCH capability for scanning app directory in
platform v3.0, we cannot use ::access. Because the capability isn't
giving permission to force out all of DAC checking, but it just bypass
to check it. So if it's checked explicitly by ::access, we cannot
bypass. So we use ::fopen with "rb" mode instead.

Change-Id: If9c79f28978ab95b607f4bffbb605f57b8b51fa9
Signed-off-by: Kyungwook Tak <k.tak@samsung.com>