Fixes crash loading combined(cert+key) certs
Fixes crash loading combined(cert+key) certs

This crash was introduced by f729c9dc41ff1635132f4bdc6331ce826f3bc2fe

pbchou/trafficserver,bryancall/trafficserver,bryancall/trafficserver,vmamidi/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,SolidWallOfCode/trafficserver,SolidWallOfCode/trafficserver,duke8253/trafficserver,SolidWallOfCode/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,duke8253/trafficserver,vmamidi/trafficserver,bryancall/trafficserver,duke8253/trafficserver,bryancall/trafficserver,duke8253/trafficserver,duke8253/trafficserver,duke8253/trafficserver,pbchou/trafficserver,duke8253/trafficserver,SolidWallOfCode/trafficserver,pbchou/trafficserver,pbchou/trafficserver,bryancall/trafficserver,pbchou/trafficserver,bryancall/trafficserver,vmamidi/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,pbchou/trafficserver