arch/i386/kernel/apm.c: apm_init() warning fix

arch/i386/kernel/apm.c: In function 'apm_init':
arch/i386/kernel/apm.c:2240: warning: format '%lx' expects type 'long
	unsigned int', but argument 3 has type 'u32'

apm_info.bios.offset is of type 'u32'.

Signed-off-by: Eugene Teo <eugeneteo@kernel.sg>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>