The option CONFIG_SND_DRIVERS is activated by default in the generic
configuration, do not deactivate it for tegra. This fixes the build of
the kmod-sound-dummy package on tegra.
(cherry picked from commit 21213c8156ccca90c135910b2ae2cdf40b8d98c3)
Link: https://github.com/openwrt/openwrt/pull/15898
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>