Replay "Add bus_dmamem_alloc_range(9) to riscv64, now required by [...]"

Unbreaks build for at least IP30.mp, otherwise kernel build breaks due to
`-Werror`:
```
[...]
cc  -g -Werror -Wall -Wimplicit-function-declaration  -Wno-uninitialized -Wno-pointer-sign  -Wframe-larger-than=2047 -mno-abicalls  -msoft-float -G 0 -ffreestanding  -O2  -pipe -nostdinc -I/sys -I/sys/arch/sgi/compile/GENERIC-IP30.MP/obj -I/sys/arch -DDDB -DDIAGNOSTIC -DKTRACE -DACCOUNTING -DKMEMSTATS -DPTRACE -DPOOL_DEBUG -DCRYPTO -DSYSVMSG -DSYSVSEM -DSYSVSHM -DUVM_SWAP_ENCRYPT -DFFS -DFFS2 -DUFS_DIRHASH -DQUOTA -DEXT2FS -DMFS -DNFSCLIENT -DNFSSERVER -DCD9660 -DUDF -DMSDOSFS -DFIFO -DFUSE -DSOCKET_SPLICE -DTCP_ECN -DTCP_SIGNATURE -DINET6 -DIPSEC -DPPP_BSDCOMP -DPPP_DEFLATE -DPIPEX -DMROUTING -DMPLS -DBOOT_CONFIG -DKERNBASE="0xa800000020000000" -DPCIVERBOSE -DUSER_PCICONF -DUSBVERBOSE -DTGT_OCTANE -DTGT_COHERENT -DARCBIOS -DCPU_R10000 -DONEWIREVERBOSE -DMULTIPROCESSOR -DMAXUSERS=32 -D_KERNEL -D__sgi__ -MD -MP  -c /sys/dev/pci/envy.c
[...]
cc1: warnings being treated as errors
/sys/dev/pci/envy.c: In function 'envy_allocm':
/sys/dev/pci/envy.c:1828: warning: implicit declaration of function 'bus_dmamem_alloc_range'
*** Error 1 in /sys/arch/sgi/compile/GENERIC-IP30.MP (Makefile:664 'envy.o')
*** Error 1 in target 'envy.o'
   14m27.69s real    23m58.74s user     3m20.45s system
2
```

See 925808a.

Author: johnny-mnemonic

sys/arch/sgi/include/bus.h

@@ -385,6 +385,9 @@ struct machine_bus_dma_tag {
 	 */
 	int	(*_dmamem_alloc)(bus_dma_tag_t, bus_size_t, bus_size_t,
 		    bus_size_t, bus_dma_segment_t *, int, int *, int);
+	int	(*_dmamem_alloc_range)(bus_dma_tag_t, bus_size_t, bus_size_t,
+		    bus_size_t, bus_dma_segment_t *, int, int *, int,
+		    paddr_t, paddr_t);
 	void	(*_dmamem_free)(bus_dma_tag_t, bus_dma_segment_t *, int);
 	int	(*_dmamem_map)(bus_dma_tag_t, bus_dma_segment_t *,
 		    int, size_t, caddr_t *, int);
@@ -419,6 +422,9 @@ struct machine_bus_dma_tag {
 
 #define	bus_dmamem_alloc(t, s, a, b, sg, n, r, f)		\
 	(*(t)->_dmamem_alloc)((t), (s), (a), (b), (sg), (n), (r), (f))
+#define bus_dmamem_alloc_range(t, s, a, b, sg, n, r, f, l, h)	\
+	(*(t)->_dmamem_alloc_range)((t), (s), (a), (b), (sg),	\
+	    (n), (r), (f), (l), (h))
 #define	bus_dmamem_free(t, sg, n)				\
 	(*(t)->_dmamem_free)((t), (sg), (n))
 #define	bus_dmamem_map(t, sg, n, s, k, f)			\

sys/arch/sgi/localbus/imc.c

@@ -172,6 +172,7 @@ struct machine_bus_dma_tag imc_bus_dma_tag = {
 	_dmamap_unload,
 	_dmamap_sync,
 	_dmamem_alloc,
+	_dmamem_alloc_range,
 	_dmamem_free,
 	_dmamem_map,
 	_dmamem_unmap,

sys/arch/sgi/localbus/macebus.c

@@ -152,6 +152,7 @@ struct machine_bus_dma_tag mace_bus_dma_tag = {
 	_dmamap_unload,
 	_dmamap_sync,
 	_dmamem_alloc,
+	_dmamem_alloc_range,
 	_dmamem_free,
 	_dmamem_map,
 	_dmamem_unmap,

sys/arch/sgi/pci/macepcibridge.c

@@ -187,6 +187,7 @@ struct machine_bus_dma_tag mace_pci_bus_dma_tag = {
 	_dmamap_unload,
 	_dmamap_sync,
 	_dmamem_alloc,
+	_dmamem_alloc_range,
 	_dmamem_free,
 	_dmamem_map,
 	_dmamem_unmap,

sys/arch/sgi/xbow/xbridge.c

@@ -547,6 +547,7 @@ static const struct machine_bus_dma_tag xbridge_dma_tag = {
 	_dmamap_unload,
 	_dmamap_sync,
 	_dmamem_alloc,
+	_dmamem_alloc_range,
 	_dmamem_free,
 	_dmamem_map,
 	_dmamem_unmap,