Segfault on phdrs allocated but not created

Segfault on phdrs allocated but not created

A number of ARM tests show results like:
ld-new: no address assigned to the veneers output section .gnu.sgstubs
ld-new: can not size stub section: invalid operation
ld-new: warning: cannot find entry symbol _start; defaulting to 0000000000010074
ld-new: tmpdir/cmse-veneers-no-gnu_sgstubs: warning: allocated section `.text' not in segment
Segmentation fault
PASS: Secure gateway veneers: no .gnu.sgstubs section

The PASS despite the segv shows the danger of using "#..." to match
error output.  This patch doesn't try to fix the testuite, but does
prevent the segfault.

	* elf.c (assign_file_positions_except_relocs): Don't segfault
	when actual number of phdrs is less than allocated.  Delete
	outdated comment.  Formatting.