liburcu: disable compilation optimizatoin

profiled applications for user-space tracing were crashing with segmentation
violation. disabling optimization for liburcu solves this problem

http://jira.alm.mentorg.com:8080/browse/SB-1143

Signed-off-by: Fahad Usman <fahad_usman@mentor.com>
Merge pull request #21 from fahadusman/sb-1143

liburcu: disable compilation optimizatoin