local.conf.sample: update distro name after merge
local.conf.sample: update distro name after merge

Newer nilrt distro is now called nilrt-nxg to distinguish it from
older nilrt (both were called "nilrt"). Older nilrt keeps the nilrt
name together with the nilrt-xfce name for the UI variant.

Signed-off-by: Ioan-Adrian Ratiu <7ec73abcfe099fc5574c01312b62768070c80980@ni.com>

ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt