ADVFS: Rename type uint_t -> u_int
ADVFS: Rename type ulong_t -> u_long
MSFS: Function prototypes with empty parameter list are invalid
MSFS: Stop assuming length of basic types (int, long..)
MSFS: Stop working-around 64-bit integer operations
MSFS: Remove unimplemented code for arches without 32-bit integers
BS: Remove work-around for arches without 32-bit integers
MSFS: Remove unused and unneeded msfs/bs_extern.h
MSFS: Remove OSF1-specific header for EVM
MSFS: Enhance const-correctness of usage C-strings
MSFS: Use NetBSD specific time constants
MSFS: Design new debug levels and functions

Replace the original:
- MS_SMP_ASSERT(),
- MS_DBG_ASSERT(),
- MS_MACRO_ASSERT(),
- ADVFS_NO_ZERO_ALLOCATE,
- MS_DEBUG_NOCOREDUMP

with a new interface:
- msfs_assert(),
- msfs_debug_assert(),
- msfs_extensive_tests().

Rename AdvfsEnableAsserts to MsfsDebugLevel for sysctl(8) levels.

Introduce new defines:
- MSFS_DEBUG (in place of ADVFS_DEBUG) and
- MSFSDEBUGLEVEL_DEFAULT.
ADVFS: Rename 'struct ucred' to 'struct uucred'
ADVFS: Remove ssDmnVerbosity relevant to missing evm
BS: Fix syntax, add missing semicolon
BS: Adapt function definition for modern C
MSFS: Set ADVFS_MIN_FREE_ACCESS=NVNODE as it's NetBSD specific
MSFS: Adapt fsid usage for NetBSD
BS: Remove unused variables
BS: Protect against unintentional assigment in if()