systemtap: Reverted dd74049

systemtap 2.3 does not need stap_linux_3.8.patch
Linux kernel 3.8 support is already there

Signed-off-by: Mikhail Durnev <mikhail_durnev@mentor.com>
Merge pull request #20 from mdurnev/mdurnev/systemtap23

systemtap: Reverted dd74049