video: agp: add remaining missing MODULE_DESCRIPTION() macros

With ARCH=i386, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/ali-agp.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/ati-agp.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/amd-k7-agp.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/efficeon-agp.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/nvidia-agp.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/agp/sworks-agp.o

Add the missing invocation of the MODULE_DESCRIPTION() macro to all
files which have a MODULE_LICENSE().

This includes alpha-agp.c and parisc-agp.c which, although they did
not produce a warning with the i386 allmodconfig configuration, may
cause this warning with other configurations.

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Helge Deller <deller@gmx.de>