pjproject: Pass (dont_)optimize flags to pjproject and fix pjsua

pjproject:  Pass (dont_)optimize flags to pjproject and fix pjsua

The pjproject Makefile now uses the Asterisk optimization flags which
are determined by the setting of the DONT_OPTMIZE menuselect flag.
The Makefile was also restructured so a change to the top level
menuselect.makeopts will result in a rebuild of pjproject.

Also, "--disable-resample" was removed from the pjproject configure
options.  Without resample, pjsua (which is used by the testsuite)
can't make audio calls.  When it can't, it segfaults.

Change-Id: I24b0a4d0872acef00ed89b3c527a713ee4c2ccd4