spi: Fix invalid sgs value

max_seg_size is unsigned int and it can have a value up to 2^32
(for eg:-RZ_DMAC driver sets dma_set_max_seg_size as U32_MAX)
When this value is used in min_t() as an integer type, it becomes
-1 and the value of sgs becomes 0.

Fix this issue by replacing the 'int' data type with 'unsigned int'
in min_t().

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220307184843.9994-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: bijudas

drivers/spi/spi.c

@@ -1019,10 +1019,10 @@ int spi_map_buf(struct spi_controller *ctlr, struct device *dev,
 	int i, ret;
 
 	if (vmalloced_buf || kmap_buf) {
-		desc_len = min_t(int, max_seg_size, PAGE_SIZE);
+		desc_len = min_t(unsigned int, max_seg_size, PAGE_SIZE);
 		sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len);
 	} else if (virt_addr_valid(buf)) {
-		desc_len = min_t(int, max_seg_size, ctlr->max_dma_len);
+		desc_len = min_t(unsigned int, max_seg_size, ctlr->max_dma_len);
 		sgs = DIV_ROUND_UP(len, desc_len);
 	} else {
 		return -EINVAL;