tools/hvmloader: Don't perform AML hotplug debugging in production

tools/hvmloader: Don't perform AML hotplug debugging in production

It is number of vmexits and a moderate quantity of qemu logging which can
safely be avoided when not specifically debugging a PCI hotplug issue.

As mk_dsdt is a build system tool, pass 'debug' as a command line parameter
rather than "hardcoding" it via the compilation of mk_dsdt itself.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Keir Fraser <keir@xen.org>
CC: Jan Beulich <JBeulich@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>