configure.ac: Use primary arch flags for openssl and libaio checks

configure.ac: Use primary arch flags for openssl and libaio checks

Make sure that the configure check for openssl/crypto and libaio use
the primary arch flags. These are used in testcases for the primary
arch and should compile and link with the primary arch flags (which
are empty on most arches, but are set explicitly on e.g. mips).

Move the libaio check after the compiler check flags.