scripts/sorttable: Add helper functions for Elf_Shdr

In order to remove the double #include of sorttable.h for 64 and 32 bit
to create duplicate functions, add helper functions for Elf_Shdr.  This
will create a function pointer for each helper that will get assigned to
the appropriate function to handle either the 64bit or 32bit version.

This also moves the _r()/r() wrappers for the Elf_Shdr references that
handle endian and size differences between the different architectures,
into the helper function and out of the open code which is more error
prone.

Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin  Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/20250105162345.940924221@goodmis.org


Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>