crypto: bcm - Rename struct device_private to bcm_device_private

crypto: bcm - Rename struct device_private to bcm_device_private

Renaming 'struct device_private' to 'struct bcm_device_private',
because it clashes with 'struct device_private' from
'drivers/base/base.h'.

While it's not a functional problem, it's causing two distinct
type hierarchies in BTF data. It also breaks build with options:
  CONFIG_DEBUG_INFO_BTF=y
  CONFIG_CRYPTO_DEV_BCM_SPU=y

as reported by Qais Yousef [1].

[1] https://lore.kernel.org/lkml/20201229151352.6hzmjvu3qh6p2qgg@e107158-lin/

Fixes: 9d12ba86f818 ("crypto: brcm - Add Broadcom SPU driver")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>