pre-proc: use uname() syscall instead of invoking uname
Not all systems have uname at /bin/uname and using uname() directly
seems to be a better case than spawning shell.
The utsname.sysname seems to be returning different name ("Linux"
instead of "GNU/Linux") but this doesn't seem to be a problem.
"uname -o" does seem to be returning HOST_OPERATING_SYSTEM and
utsname.sysname being defined as KERNEL_NAME.
Signed-off-by: Andrey Albersteyn <aalbersh@redhat.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>