[PATCH 4.19.6] BFS: static inode bitmap and extra sanity checking

Hello,

Please find a patch attached which contains the following changes:

1. Simplifies inode bitmap allocation by making it static. 2. Supersedes the changes to BFS that went into 4.19.6 with stronger checking. 3. Other changes are trivial (like whitespace cleanup, warning messages etc).

Fully tested under 4.19.6 kernel.

Kind regards, Tigran