Documentation/powerpc: Mention 40x is removed

Commit 732b32da ("powerpc: Remove core support for 40x") removed 40x.

Update documentation accordingly.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/c2d64bebc514ca892a12e51a68821a6317048d3a.1720694954.git.christophe.leroy@csgroup.eu

Documentation/arch/powerpc/cpu_families.rst

@@ -128,24 +128,6 @@ IBM BookE
 - All 32 bit::
 
    +--------------+
-   |     401      |
-   +--------------+
-          |
-          |
-          v
-   +--------------+
-   |     403      |
-   +--------------+
-          |
-          |
-          v
-   +--------------+
-   |     405      |
-   +--------------+
-          |
-          |
-          v
-   +--------------+
    |     440      |
    +--------------+
           |

Documentation/arch/powerpc/elf_hwcaps.rst

@@ -91,6 +91,7 @@ PPC_FEATURE_HAS_MMU
 
 PPC_FEATURE_HAS_4xxMAC
     The processor is 40x or 44x family.
+    Unused in the kernel since 732b32daef80 ("powerpc: Remove core support for 40x")
 
 PPC_FEATURE_UNIFIED_CACHE
     The processor has a unified L1 cache for instructions and data, as