rpmsg: glink: Fix GLINK command prefix

[ Upstream commit 4e816d0318fdfe8932da80dbf04ba318b13e4b3a ]

The upstream GLINK driver was first introduced to communicate with the
RPM on MSM8996, presumably as an artifact from that era the command
defines was prefixed RPM_CMD, while they actually are GLINK_CMDs.

Let's rename these, to keep things tidy. No functional change.

Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Chris Lew <quic_clew@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230214225933.2025595-1-quic_bjorande@quicinc.com


Stable-dep-of: 06c59d97f63c ("rpmsg: glink: use only lower 16-bits of param2 for CMD_OPEN name length")
Signed-off-by: Sasha Levin <sashal@kernel.org>