add uio_find_by_uio_name

The last release was broken in various ways. First the declaration of the new
function uio_find_by_uio_name() was missing in libuio.h. Second the library
version number was not updated at all. Sorry for the inconvenience.

Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
add readuio

add a small test application to read one or more registers of a UIO device.

Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
add map name functions

UIO maps have a name. Add convinient functions to convert a map name into
a map number and vice versa.

Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
add missing if in uio_get_bin_attr

otherwise the function call fails always

Signed-off-by: Manuel Traut <manut@linutronix.de>
Merge changes from Manuel Traut <manut@linutronix.de> into devel