binfmt_elf_fdpic: fix AUXV size calculation when ELF_HWCAP2 is defined

In the Linux kernel, the following vulnerability has been resolved:

binfmt_elf_fdpic: fix AUXV size calculation when ELF_HWCAP2 is defined

create_elf_fdpic_tables() does not correctly account the space for the

AUX vector when an architecture has ELF_HWCAP2 defined. Prior to the

commit 10e29251be0e ("binfmt_elf_fdpic: fix /proc/<pid>/auxv") it

resulted in the last entry of the AUX vector being set to zero, but with

that change it results in a kernel BUG.

Fix that by adding one to the number of AUXV entries (nitems) when

ELF_HWCAP2 is defined.