Pacify -Wanalyzer-use-of-uninitialized-value

Pacify -Wanalyzer-use-of-uninitialized-value

With ‘configure --enable-gcc-warnings’,
gcc (GCC) 14.2.1 20250110 (Red Hat 14.2.1-7) on x86-64
complained, as it apparently did not want to assume that enum
variables have one of the listed values.
Work around the problem by using tables rather than
switch statements.  This gives up a little static
checking but I don’t see any other easy way to pacify
GCC without disabling the warnings entirely.
* src/pdumper.c (dump_fwd_int, dump_fwd_bool, dump_fwd_obj)
(dump_fwd_buffer_obj, dump_fwd_kboard_obj):
Last arg is now void const * so that these functions’ addresses
can all be put into the same array.
(dump_fwd, dump_anonymous_allocate_posix, dump_map_file_posix):
Use an array rather than a switch.
(mem_prot_posix_table): New static constant table.

(cherry picked from commit 1ed769a3cb753a86badba8a2878fa788a6fdc1f8)