jtag: move prototype of adapter init/quit and speed to adapter.h

After moved the code, align the include files.

Change-Id: I514a3020648816810d69f76c2ec4f6e52a1c57ab
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6643
Tested-by: jenkins
Reviewed-by: Tarek BOCHKATI <tarek.bouchkati@gmail.com>

src/target/mips64_pracc.c

@@ -21,6 +21,7 @@
 #include "mips64_pracc.h"
 
 #include <helper/time_support.h>
+#include <jtag/adapter.h>
 
 #define STACK_DEPTH	32