riscv: rename sptbr to satp

satp is the name used by the current privileged spec 1.10, use it
instead of the old name.  The most recent release binutils release
(2.29) doesn't know about the satp name yet, so stick to the name from
the previous privileged ISA release and comment on the fact.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

arch/riscv/include/asm/csr.h

@@ -40,15 +40,15 @@
 #define SR_SD   _AC(0x8000000000000000, UL) /* FS/XS dirty */
 #endif
 
-/* SPTBR flags */
+/* SATP flags */
 #if __riscv_xlen == 32
-#define SPTBR_PPN     _AC(0x003FFFFF, UL)
-#define SPTBR_MODE_32 _AC(0x80000000, UL)
-#define SPTBR_MODE    SPTBR_MODE_32
+#define SATP_PPN     _AC(0x003FFFFF, UL)
+#define SATP_MODE_32 _AC(0x80000000, UL)
+#define SATP_MODE    SATP_MODE_32
 #else
-#define SPTBR_PPN     _AC(0x00000FFFFFFFFFFF, UL)
-#define SPTBR_MODE_39 _AC(0x8000000000000000, UL)
-#define SPTBR_MODE    SPTBR_MODE_39
+#define SATP_PPN     _AC(0x00000FFFFFFFFFFF, UL)
+#define SATP_MODE_39 _AC(0x8000000000000000, UL)
+#define SATP_MODE    SATP_MODE_39
 #endif
 
 /* Interrupt Enable and Interrupt Pending flags */