IRBuilder sets all 2 reg branches as switch branches, fix this
IRBuilder sets all 2 reg branches as switch branches, fix this

IRBuilder is setting the flag m_isSwitchBr for all 2 register branch
instructions. Fixing this.

mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore