package_deb.bbclass:fix the arch (replace "_" with "-") in deb package control

package_deb.bbclass:fix the arch (replace "_" with "-") in deb package control

when build deb image, such as building meta-toolchain-sdk in x86_64 host,
there is warning like that:
...
'x86_64' is not a valid architecture name: character `_' not allowed
(only letters, digits and characters `-')
...

The params in deb package control file don't allow character `_', only
letters, digits and characters `-' allowed. Change the arch's "_" to "-"
in the deb package's control file at the control file creation time. Such
as `x86_64'-->`x86-64'

[YOCTO #3721]

(From OE-Core rev: 8487b352cabd8c8ae8a7d9e7e66489e4e964bd50)

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