Make hard-wired TLB allocations be at minimum one page. This is required by
some implementations, most notably (in my case) QEMU's e500 emulation.
Remove the isf(4) driver.  It was created by accident and is subset of
the cfi(4) driver.  It remained in the tree longer than would be ideal
due to the time required to bring cfi(4) to feature parity.

Sponsored by:	DARPA/AFRL
MFC after:	3 days
Resolve clang warning about a use of syslog. By using a proper enforcement
of string format in a call so syslog

/usr/src/gnu/lib/libssp/../../../contrib/gcclibs/libssp/ssp.c:137:23:
warning: format string is not a string literal (potentially insecure)
      [-Wformat-security]
    syslog (LOG_CRIT, msg1);
                      ^~~~

Reviewed by:	dim@