firmware: imx: scu-pd: Rename mu PD range to mu_a

The Messaging Unit module enables two processors within the SoC to
communicate and coordinate by passing messages through the MU interface.

MUs have 2 “sides” with independent programming interfaces. Rename
mu PD range to mu_a because it's actually side A of MUs.
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/firmware/imx/scu-pd.c

@@ -92,7 +92,7 @@ static const struct imx_sc_pd_range imx8qxp_scu_pd_ranges[] = {
 	{ "gpt", IMX_SC_R_GPT_0, 5, true, 0 },
 	{ "kpp", IMX_SC_R_KPP, 1, false, 0 },
 	{ "fspi", IMX_SC_R_FSPI_0, 2, true, 0 },
-	{ "mu", IMX_SC_R_MU_0A, 14, true, 0 },
+	{ "mu_a", IMX_SC_R_MU_0A, 14, true, 0 },
 
 	/* CONN SS */
 	{ "usb", IMX_SC_R_USB_0, 2, true, 0 },