elf: Support at least 32-byte alignment in static dlopen

Otherwise loading a dynamically linked libc with rseq support fails,
as result of the __rseq_abi TLS variable, which has an alignment
of 32 bytes.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Alistair Francis <alistair.francis@wdc.com>