adapter: use bitmask for driver's transports

In every driver, replace the array of strings with a bitmask that
lists the supported transports.
Add an extra field to carry the former first listed transport as a
"preferred" transport. It would be used as default when no command
'transport select' is used. This keeps backward compatibility with
scripts that do not define the transport, relying on such default.

Change-Id: I4976583f1a38fdcc1f85045023dc7c629001f743
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/8675
Tested-by: jenkins
Reviewed-by: zapb <dev@zapb.de>

src/jtag/interface.h

@@ -17,6 +17,7 @@
 #include <jtag/jtag.h>
 #include <jtag/swim.h>
 #include <target/arm_tpiu_swo.h>
+#include <transport/transport.h>
 
 /* @file
  * The "Cable Helper API" is what the cable drivers can use to help
@@ -208,8 +209,16 @@ struct adapter_driver {
 	/** The name of the interface driver. */
 	const char * const name;
 
-	/** transports supported in C code (NULL terminated vector) */
-	const char * const *transports;
+	/**
+	 * Bitmask of transport IDs supported in C code.
+	 */
+	unsigned int transport_ids;
+
+	/**
+	 * ID of transport that gets auto-selected when not specified by the user.
+	 * The auto-selection of transport is DEPRECATED.
+	 */
+	unsigned int transport_preferred_id;
 
 	/**
 	 * The interface driver may register additional commands to expose
@@ -354,8 +363,6 @@ struct adapter_driver {
 	const struct swim_driver *swim_ops;
 };
 
-extern const char * const jtag_only[];
-
 int adapter_resets(int assert_trst, int assert_srst);
 int adapter_assert_reset(void);
 int adapter_deassert_reset(void);