net/ipv6: Remove unnecessary pr_debug() logs

net/ipv6: Remove unnecessary pr_debug() logs

In the ipv6 system, we have some logs basically dumping the name of the
function that is being called. This is not ideal, since ftrace give us
"for free". Moreover, checkpatch is not happy when touching that code:

	WARNING: Unnecessary ftrace-like logging - prefer using ftrace

Remove debug functions that only print the current function name.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240122181955.2391676-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>