Changed Inode ID bounds check

[jvff]

In "kernel_interface.cpp", I changed the Inode ID bounds so it would limit the Inode ID to the maximum number of Inodes in the file system. It also contains a superblock check to see if it indicates that the file system has errors.

[axeld]

I like it, but I have one coding style remark, and one suggestion:

• Multiline statements after an if/for/while should be enclosed in curly braces.
• Instead of using something like State() == 2, define constants for the known states, and check against those.

Thanks!

[jvff]

Patch containing only changes relative to inode bounds checking.

[korli]

Applied in hrev36358.