net: tsec - fix dereferencing type-punned pointer will break strict-aliasing rules warning

fix this gcc 4.4 warning:

tsec.c: In function 'tsec_init':
tsec.c:200: warning: dereferencing type-punned pointer will break strict-aliasing rules

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>