base: Delete an inet.hh accessor which is unused and makes gcc 9 upset.

base: Delete an inet.hh accessor which is unused and makes gcc 9 upset.

This accessor will return a pointer to an unaligned uint32_t. Since
it's not used and it's not clear how to fix it trivially, this change
just deletes it.

Change-Id: I08bc62276d639cc728411f3a8a23be385000ebab
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24925
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>