epiphany: Fix driver error reporting

Add catch-all statement to mmap handler so we know when a user does an
invalid request.

Add newlines to printk messages so they appear immediately in kernel
log (line buffering).

Reduce severity of some printk messages to DEBUG.

Signed-off-by: Ola Jeppsson <ola@adapteva.com>
epiphany: Fix typo in mmap range check

Make mmap behave the intended way.

Signed-off-by: Ola Jeppsson <ola@adapteva.com>
Merge pull request #3 from parallella/pr-epiphany-driver-fixes

Epiphany driver fixes