drm: kirin: Move request irq handle in ade hw ctx alloc

As part of refactoring the kirin driver to better support
different hardware revisions, this patch modifies the
initialization routines so the devm_request_irq() function
is called as part of the allocation function.

This will be needed in the future when we will have different
allocation functions to allocate hardware specific hw_ctx
structures, which will setup the vblank irq differently.

Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Xu YiPing <xuyiping@hisilicon.com>
[jstultz: reworded commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190820230626.23253-10-john.stultz@linaro.org