if installed into a path that contains the $ARCH name, the default pantask paths become corrupted

[jhoblitt]

When attempting to install Ohana under the prefix
/home/moanui/jhoblitt/jhroot/i686-pc-linux-gnu on linux the default path for
pantasks scripts becomes corrupted. The cause seems to be that gcc is passed
-Dlinux -D[path] when building pantasks.c. CPP is then interpolating the string
"linux" in [path] to the value "1". Thus, the default path for pantasks scripts
becomes transliterated to /home/moanui/jhoblitt/jhroot/i686-pc-1-gnu.

[eugene]

done: the relevant path is now supplied with a perl script that parses the mana.c.in file (and equivalents) and creates the output mana.c file. the -Dpath is no longer used.