kernel: fix warning when building fitblk on 32-bit platforms

Kernel warns about comparision of different types without cast when
building the fitblk driver on 32-bit platforms.
Fix this by using `min_t(size_t, ...`.

Fixes: 8fc5457869 ("kernel: add pending fitblk uImage.FIT sub-image block driver")
Signed-off-by: Daniel Golle <[email protected]>

target/linux/generic/pending-6.1/510-block-add-uImage.FIT-subimage-block-driver.patch

@@ -81,7 +81,7 @@ Signed-off-by: Daniel Golle <[email protected]>
  swim_mod-y	:= swim.o swim_asm.o
 --- /dev/null
 +++ b/drivers/block/fitblk.c
-@@ -0,0 +1,635 @@
+@@ -0,0 +1,636 @@
 +// SPDX-License-Identifier: GPL-2.0-only
 +/*
 + * uImage.FIT virtual block device driver.
@@ -454,7 +454,8 @@ Signed-off-by: Daniel Golle <[email protected]>
 +	bytes_left = size;
 +	fit_c = fit;
 +	while (bytes_left > 0) {
-+		bytes_to_copy = min(bytes_left, folio_size(folio) - offset_in_folio(folio, 0));
++		bytes_to_copy = min_t(size_t, bytes_left,
++				     folio_size(folio) - offset_in_folio(folio, 0));
 +		memcpy(fit_c, pre_fit, bytes_to_copy);
 +		fit_c += bytes_to_copy;
 +		bytes_left -= bytes_to_copy;