* Add code for formal master/slave checking rules as defined in ports/64393 [1]:
1. A port is a slave port if and only if MASTERDIR != .CURDIR
2. Slave ports should define MASTERDIR using one of the following lines:
MASTERDIR= ${.CURDIR}/../../<category>/<port>
MASTERDIR= ${.CURDIR}/../<port>
3. Non-slave ports shouldn't define MASTERDIR at all
4. The last line of a slave port's Makefile has to be
.include "${MASTERDIR}/Makefile"
5. The last line of a non-slave ports Makefile must be one of:
.include <bsd.port.mk>
.include <bsd.port.post.mk>
6. slave ports may not include bsd.port(.pre).mk
* Check to make sure MACHINE_ARCH is not defined and make sure it is never
tested directly [2]
* Fix some grammar nits [3]
PR: 64420 [1]
Submitted by: eik [1]
krion [3]
Requested by: kris [2]
31441bb2d6