v26.02

common/cnxk: fix cnxk xstats names

Prevent out of bounds writes when application provides a smaller
xstat name array. Return required count when xstats_names is NULL
or when the provided buffer is too small,

Fixes: 825bd1d9d8e6 ("common/cnxk: update extra stats for inline device")

Signed-off-by: Alok Mishra <almishra@marvell.com>