Use major/minor macros from sys/sysmacros.h instead of linux/kdev_t.h
Use major/minor macros from sys/sysmacros.h instead of linux/kdev_t.h

The macros from linux/kdev_t.h don't work for devices with
minor > 255.

Resolves: rhbz#1644825

rhinstaller/libblockdev,rhinstaller/libblockdev,rhinstaller/libblockdev