devel/raylib: Install missing header files

[otis]

Summary

It has been noticed that this port does not install some of the crucial header
files, this is also confirmed by the plist. The missing headers are from what I
can gather:

• raymath.h
• rlgl.h
• physac.h

Along with corrected plist, also PORTREVISION has been bumped.

PR: 251819
Reported by: Mattias Wikstrom <[e-mail]>
Submitted by: Martin Filla <[e-mail]> (maintainer)

[osa]

The patch looks good and I'd recommend to use ${INSTALL_DATA} instead of ${CP} command in the pre-install target.

[otis]

In D27776#620799, @osa wrote:

The patch looks good and I'd recommend to use ${INSTALL_DATA} instead of ${CP} command in the pre-install target.

I've already had ${INSTALL_DATA} in consideration but dropped that for unknown reasons.
The other thing is that the pre-install target could/shout be moved to post-install (to let the respective make install begin in clean stage directory, not polluted with these three .h files).

Other than that I will also run a poudriere job for this (I did not do the tests myself at the moment, only the maintainer has been asked to do so).

[otis]

Replace ${CP} with ${INSTALL_DATA} and move pre-install to post-install to let install target begin with clean stage directory.

[osa]

Looks good to me.