Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "12 patches.

  Subsystems affected by this patch series: mm (documentation, kasan,
  and pagemap), csky, ia64, gcov, and lib"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib: remove "expecting prototype" kernel-doc warnings
  gcov: clang: fix clang-11+ build
  mm: ptdump: fix build failure
  mm/mapping_dirty_helpers: guard hugepage pud's usage
  ia64: tools: remove duplicate definition of ia64_mf() on ia64
  ia64: tools: remove inclusion of ia64-specific version of errno.h header
  ia64: fix discontig.c section mismatches
  ia64: remove duplicate entries in generic_defconfig
  csky: change a Kconfig symbol name to fix e1000 build error
  kasan: remove redundant config option
  kasan: fix hwasan build for gcc
  mm: eliminate "expecting prototype" kernel-doc warnings