4.3.0int6 will not compile with --disable-hpi flag

[ltyndale]

When trying to compile V4.3.0int6 without HPI support using the --disable-hpi option when running configure, the compile fails with the following error:

file included from ../rdhpi/rdhpiplaystream.h:35,
from hpiplayout_test.h:29,
from hpiplayout_test.cpp:26:
../rdhpi/rdhpisoundcard.h:34:10: fatal error: asihpi/hpi.h: No such file or directory
34 | #include <asihpi/hpi.h>
| ^~~~~~~~~~~~~~
compilation terminated.
make[1]: *** [Makefile:991: hpiplayout_test.o] Error 1
make[1]: Leaving directory '/home/rd/rivendell-4/tests'
make: *** [Makefile:552: all-recursive] Error 1

This is not an issue in V4.3.0int5

The output of configure
configure: "| *** RIVENDELL CONFIGURATION SUMMARY *** |"
configure: "|---------------------------------------------------------|"
configure: "| Platform Information: |"
configure: "| Distribution Name ... Ubuntu |"
configure: "| Distribution Family ... Debian |"
configure: "| Update I18N Data ... No |"
configure: "| |"
configure: "| Configured Audio Drivers: |"
configure: "| Advanced Linux Sound Architecture (ALSA) ... Yes |"
configure: "| AudioScience HPI ... No |"
configure: "| JACK Audio Connection Kit ... Yes |"
configure: "| |"
configure: "| Audio Codecs: |"
configure: "| FLAC Encoding/Decoding Support ... Yes |"
configure: "| MPEG Decoding Support ... Yes |"
configure: "| MPEG Layer 2 Encoding Support ... Yes |"
configure: "| MPEG Layer 3 Encoding Support ... Yes |"
configure: "| OggVorbis Encoding/Decoding Support ... Yes |"
configure: "| M4A Decoding Support ... No |"
configure: "|---------------------------------------------------------|"