memory: renesas-rpc-if: Drop usage of RPCIF_DIRMAP_SIZE macro

RPCIF_DIRMAP_SIZE may differ on various SoC's. Instead of using
RPCIF_DIRMAP_SIZE macro use resource size to get dirmap size
which is already part of struct rpcif.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211025205631.21151-7-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

drivers/memory/renesas-rpc-if.c

@@ -147,8 +147,6 @@
 #define RPCIF_PHYINT		0x0088	/* R/W */
 #define RPCIF_PHYINT_WPVAL	BIT(1)
 
-#define RPCIF_DIRMAP_SIZE	0x4000000
-
 static const struct regmap_range rpcif_volatile_ranges[] = {
 	regmap_reg_range(RPCIF_SMRDR0, RPCIF_SMRDR1),
 	regmap_reg_range(RPCIF_SMWDR0, RPCIF_SMWDR1),
@@ -588,8 +586,8 @@ static void memcpy_fromio_readw(void *to,
 
 ssize_t rpcif_dirmap_read(struct rpcif *rpc, u64 offs, size_t len, void *buf)
 {
-	loff_t from = offs & (RPCIF_DIRMAP_SIZE - 1);
-	size_t size = RPCIF_DIRMAP_SIZE - from;
+	loff_t from = offs & (rpc->size - 1);
+	size_t size = rpc->size - from;
 
 	if (len > size)
 		len = size;