arm64: Documentation: cpu-feature-registers: Remove RES0 fields

Remove the invisible RES0 field entries from the table, listing
fields in CPU ID feature registers, as :
 1) We are only interested in the user visible fields.
 2) The field description may not be up-to-date, as the
    field could be assigned a new meaning.
 3) We already explain the rules of the fields which are not
    visible.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Documentation/arm64/cpu-feature-registers.txt

@@ -110,7 +110,6 @@ infrastructure:
      x--------------------------------------------------x
      | Name                         |  bits   | visible |
      |--------------------------------------------------|
-     | RES0                         | [63-52] |    n    |
      |--------------------------------------------------|
      | FHM                          | [51-48] |    y    |
      |--------------------------------------------------|
@@ -124,8 +123,6 @@ infrastructure:
      |--------------------------------------------------|
      | RDM                          | [31-28] |    y    |
      |--------------------------------------------------|
-     | RES0                         | [27-24] |    n    |
-     |--------------------------------------------------|
      | ATOMICS                      | [23-20] |    y    |
      |--------------------------------------------------|
      | CRC32                        | [19-16] |    y    |
@@ -135,8 +132,6 @@ infrastructure:
      | SHA1                         | [11-8]  |    y    |
      |--------------------------------------------------|
      | AES                          | [7-4]   |    y    |
-     |--------------------------------------------------|
-     | RES0                         | [3-0]   |    n    |
      x--------------------------------------------------x
 
 
@@ -144,12 +139,9 @@ infrastructure:
      x--------------------------------------------------x
      | Name                         |  bits   | visible |
      |--------------------------------------------------|
-     | RES0                         | [63-36] |    n    |
      |--------------------------------------------------|
      | SVE                          | [35-32] |    y    |
      |--------------------------------------------------|
-     | RES0                         | [31-28] |    n    |
-     |--------------------------------------------------|
      | GIC                          | [27-24] |    n    |
      |--------------------------------------------------|
      | AdvSIMD                      | [23-20] |    y    |