Do not fail when data is missing in /proc/cpuinfo
CTestXML2HTML fails on ARM because /proc/cpuinfo does not contain the same information as on intel there. e.g. on a thunderx with centos7 and kernel 5.4.0-47-generic, I get:
processor : 0
BogoMIPS : 400.00
Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics cpuid asimdrdm
CPU implementer : 0x43
CPU architecture: 8
CPU variant : 0x1
CPU part : 0x0af
CPU revision : 1
The command therefore CTestXML2HTML fails due to missing index in map.