[COOK-3763] Prevent "openjdk" recipe failing on CentOS 6.

The error is caused by an incorrect glob in the "update-java-alternatives" block.

Since the code in the block is too complex to attempt to fix the root cause,
the provided patch only ensures the code does not fail unnecessarily.

The ticket is at: http://tickets.opscode.com/browse/CHEF-3763

Closes #31
Merge pull request #31 from karmi/openjdk-update-alternatives-fix

[COOK-3763] Prevent "openjdk" recipe failing on CentOS 6.