acpica: use update-alternatives for acpidump

acpidump is both provided by acpica and pmtools, so use
update-alternatives to fix conflicts:
...
|Error: Transaction check error:
|  file /usr/bin/acpidump conflicts between attempted installs of
pmtools-20130209+git0+3ebe0e54c5-r0.i586 and acpica-20190405-r0.i586
...

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>