'cap' is an enum, thus cast of pointer on 64-bit compile test with W=1
causes:

  hidma.c:748:8: error: cast to smaller integer type 'enum hidma_cap' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230810100000.123515-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>