x86/srat: fix end calculation in nodes_cover_memory()

x86/srat: fix end calculation in nodes_cover_memory()

Along the lines of commit 7226486767 ("x86/srat: fix the end pfn check
in valid_numa_range()") nodes_cover_memory() also doesn't consistently
use "end": It's set to an inclusive value initially, but then compared
to the exclusive "end" field of struct node and also possibly set to
nodes[j].start, making it exclusive too. Change the initialization to
make the variable consistently exclusive.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>