arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0

Double lock feature can have the following possible values.

0b0000 - Double lock implemented
0b1111 - Double lock not implemented

But in case of a conflict the safe value should be 0b1111. Hence this must
be a signed feature instead. Also change FTR_EXACT to FTR_LOWER_SAFE. While
here, fix the erroneous bit width value from 28 to 4.

Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Suzuki K Poulose <[email protected]>
Cc: [email protected]
Cc: [email protected]

Suggested-by: Suzuki K Poulose <[email protected]>
Signed-off-by: Anshuman Khandual <[email protected]>
Reviewed-by: Suzuki K Poulose <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

0 files changed, 0 insertions, 0 deletions