staging: most: define iface_to_hdm as an inline function

Convert `iface_to_hdm` macro into a static inline function.
it is not great to have macro that use `container_of` macro,
because from looking at the definition one cannot tell
what type it applies to.

One can get the same benefit from an efficiency point of view
by making an inline function.
Suggested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Menna Mahmoud <eng.mennamahmoud.mm@gmail.com>
Link: https://lore.kernel.org/r/20230320212239.22452-1-eng.mennamahmoud.mm@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/most/dim2/dim2.c

@@ -108,7 +108,10 @@ struct dim2_platform_data {
 	u8 fcnt;
 };
 
-#define iface_to_hdm(iface) container_of(iface, struct dim2_hdm, most_iface)
+static inline struct dim2_hdm *iface_to_hdm(struct most_interface *iface)
+{
+	return container_of(iface, struct dim2_hdm, most_iface);
+}
 
 /* Macro to identify a network status message */
 #define PACKET_IS_NET_INFO(p)  \