media: mtk_jpeg_core: avoid unused-variable warning

The mtk8195_jpegenc_drvdata object was added outside of an #ifdef causing
a harmless build warning.

drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c:1879:32: error: 'mtk8195_jpegenc_drvdata' defined but not used [-Werror=unused-variable]
 1879 | static struct mtk_jpeg_variant mtk8195_jpegenc_drvdata = {
      |                                ^~~~~~~~~~~~~~~~~~~~~~~

A follow-up patch moved it inside of an #ifdef, which caused more
warnings, and a third patch ended up adding even more #ifdefs. These
were all bogus, since the actual problem here is the incorrect use
of of_ptr(). Since the driver (like any other modern platform driver)
only works in combination with CONFIG_OF, there is no point in hiding
the reference, so just remove that along with all the pointless #ifdef
checks in the driver.

This improves build coverage and avoids running into the same problem
again when another part of the driver gets changed that relies on
the #ifdef blocks to be completely matched.

Fixes: 934e8bcc ("mtk-jpegenc: support jpegenc multi-hardware")
Fixes: 4ae47770 ("media: mtk-jpegenc: Fix a compilation issue")
Fixes: da4ede4b ("media: mtk-jpeg: move data/code inside CONFIG_OF blocks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>