- Deprecate PCIR_MAPS under BURN_BRIDGES (meaning it will be gone in 6.0)

and replace it with the more intuitive name PCIR_BARS.
- Add a PCIR_BAR(x) macro that returns the config space register offset of
  the 32-bit BAR x.

MFC after:	3 days

sys/dev/pci/pcireg.h

@@ -100,7 +100,11 @@
 
 /* config registers for header type 0 devices */
 
-#define PCIR_MAPS	0x10
+#define PCIR_BARS	0x10
+#define	PCIR_BAR(x)	(PCIR_BARS + (x) * 4)
+#ifndef BURN_BRIDGES
+#define	PCIR_MAPS	PCIR_BARS
+#endif
 #define PCIR_CARDBUSCIS	0x28
 #define PCIR_SUBVEND_0	0x2c
 #define PCIR_SUBDEV_0	0x2e