fix boot failure on 32-bit systems caused by branch stubs placed before .text

fix boot failure on 32-bit systems caused by branch stubs placed before .text

commit ed5fb2471b7060767957fb964eb1aaec71533ab1 upstream.

In certain configurations, the resulting kernel becomes too large to boot
because the linker places the long branch stubs for the merged .text section
at the very start of the image.  As a result, the initial transfer of control
jumps to an unexpected location.  Fix this by placing the head text in a
separate section so the stubs for .text are not at the start of the image.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>