fix dwarf2read.c offset-is-in-cu calculation

[Daniel Jacobowitz]

On Sat, Oct 04, 2008 at 01:54:03PM -0700, Doug Evans wrote:
> Some calculations for whether an offset is within a CU don't take into
> account initial_length_size.
> The error is innocuous because GDB will still lookup the correct CU,
> but it didn't have to do the lookup.  The error also causes the CU
> to be made a dependency of itself which is unnecessary.
> 
> This also changes the name of a label in dw2-intercu.S to improve
> readability.
> 
> Ok to check in?

OK.

-- 
Daniel Jacobowitz
CodeSourcery