gitk: Use the UI font for the diff/old version/new version radio buttons
gitk: Use the UI font for the diff/old version/new version radio buttons

This makes the radio buttons for selecting whether to see the full diff,
the old version or the new version use the same font as the other user
interface elements.

Signed-off-by: Paul Mackerras <19a0ba370c443ba08d20b5061586430ab449ee8c@samba.org>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git