build/pkgs/gap/SPKG.rst: Remove outdated info

Signed-off-by: Michael Orlitzky <michael@orlitzky.com>

build/pkgs/gap/SPKG.rst

@@ -25,26 +25,3 @@ Upstream Contact
 https://www.gap-system.org
 
 Mailing list at https://mail.gap-system.org/mailman/listinfo/gap
-
-Special Update/Build Instructions
----------------------------------
-
-This is a stripped-down version of GAP. The downloading of the sources
-and removal of unneeded parts is done by the script spkg-src. When you
-update GAP, please also update and use the spkg-src script.
-
--  Do we really want to copy everything from the build directory???
-
-   You need the full GAP tree to compile/install many GAP packages.
-
--  There's apparently a command missing (in ``spkg-install``) building
-   the
-   (HTML?) documentation. Earlier changelog entries as well as the
-   description
-   above state the documentation was removed from the upstream
-   sources...
-   Since the (pre-)built HTML documentation is currently included, I've
-   commented out some lines in that part of ``spkg-install``. -leif
-
-Patches
-~~~~~~~