um: Rework uaccess code

Rework UML's uaccess code to reuse as much as possible
from asm-generic/uaccess.c.

Signed-off-by: Richard Weinberger <richard@nod.at>

diff --cc arch/um/include/asm/thread_info.h
Simple merge

diff --cc arch/um/include/asm/uaccess.h
Simple merge

diff --cc arch/um/kernel/skas/uaccess.c
Simple merge

diff --cc arch/x86/um/asm/checksum.h
Simple merge

diff --cc arch/x86/um/asm/elf.h
Simple merge

diff --cc arch/x86/um/asm/processor.h
Simple merge

diff --cc arch/x86/um/asm/segment.h
Simple merge