The tile vDSO vsyscalls were not properly setting the error value.
Conventionally, tile returns the same "non-negative success, negative
errno" value that x86 does (in r0), but it also returns "zero or positive
errno" in r1, which is what the regular syscall code checks. This change
uses that convention for the vDSO calls as well.
I've moved the TILE-Gx and TILEPro ports to the main sysdeps hierarchy,
along with the linux-generic ports infrastructure. Beyond the README
update, the move was just
git mv ports/sysdeps/tile sysdeps/tile
git mv ports/sysdeps/unix/sysv/linux/tile \
sysdeps/unix/sysv/linux/tile
git mv ports/sysdeps/unix/sysv/linux/generic \
sysdeps/unix/sysv/linux/generic
I updated the relevant ChangeLogs along the lines of the ARM move
in commit c6bfe5c4d7 and tested the 64-bit tilegx build to confirm that
there were no changes in "objdump -dr" output in the shared objects.
