This commit fixes a bug in the timer check. When -fPIC is used we need
to save/restore ebx. The code copied from patcher was meant for 32-bit
systems and did not work correctly on 64-bit systems. This commit
updates the save/restore to use rbx instead of ebx.
Fixes#2678
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>