SOLARIS: Fix platforms for KOBJ definition

SOLARIS: Fix platforms for KOBJ definition

Currently, we define KOBJ to "MODLOAD32 MODLOAD64" for the following
platforms:

<all -sun4x_510 sun4x_511 sunx86_511>

Which doesn't make any sense, since "all" includes sun4x_511 and
sunx86_511. The previous commits that modified this line, e4c2810f
(Remove support for Solaris pre-8) and c6a22d67 (SOLARIS: Do not build
x86 kernel module on 5.11), clearly meant to change the platforms
sun4x_511 and sunx86_511 to use the KOBJ on the next line, but omitted
the leading "-" for the platform.

This doesn't break anything, since the Makefile on these platforms
expands to:

    KOBJ = MODLOAD32 MODLOAD64
    KOBJ = MODLOAD64

So the first KOBJ line is effectively ignored. It's confusing, though,
so fix this line so these platforms only get one KOBJ definition.

Change-Id: Idea9fdee4ac5883428748c2a5fdfa9707406436a
Reviewed-on: https://gerrit.openafs.org/13343
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>