The DoH spec says "HTTP/2 [RFC7540] is the minimum RECOMMENDED version of HTTP for use with DoH". Reported-by: Marcel Raad Closes #3066
The gcc typecheck macros and coverity combined made it warn on the 2nd argument for ERROR_CHECK_SETOPT(). Here's minor rearrange to please it. Coverity CID 1439115 and CID 1439114.
Closes #2668
