Another dependency problem: radeon (also?) depends on agp

[Paul Goyette <paul%whooppee.com@localhost>]

I've also discovered that if you have a radeon, you also need to have

	agp* at pchb?

configured.  Otherwise you get the following errors while compiling 
radeon_ttm.c

/build/netbsd-local/src/sys/external/bsd/drm2/dist/drm/radeon/radeon_ttm.c: In function 'radeon_ttm_tt_populate':
/build/netbsd-local/src/sys/external/bsd/drm2/dist/drm/radeon/radeon_ttm.c:612:24: error: variable 'rdev' set but not used [-Werror=unused-but-set-variable]
  struct radeon_device *rdev;
                        ^
/build/netbsd-local/src/sys/external/bsd/drm2/dist/drm/radeon/radeon_ttm.c: In function 'radeon_ttm_tt_unpopulate':
/build/netbsd-local/src/sys/external/bsd/drm2/dist/drm/radeon/radeon_ttm.c:677:24: error: variable 'rdev' set but not used [-Werror=unused-but-set-variable]
  struct radeon_device *rdev;
                        ^
cc1: all warnings being treated as errors


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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
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