fsdax: remove redundant variable 'error'

The variable 'error' is being assigned a value that is never read,
the assignment and the variable and redundant and can be removed.
Cleans up clang scan build warning:

fs/dax.c:1880:10: warning: Although the value stored to 'error' is
used in the enclosing expression, the value is never actually read
from 'error' [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20230621130256.2676126-1-colin.i.king@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

Author: ColinIanKing

fs/dax.c

@@ -1830,7 +1830,6 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 	vm_fault_t ret = VM_FAULT_FALLBACK;
 	pgoff_t max_pgoff;
 	void *entry;
-	int error;
 
 	if (vmf->flags & FAULT_FLAG_WRITE)
 		iter.flags |= IOMAP_WRITE;
@@ -1877,7 +1876,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 	}
 
 	iter.pos = (loff_t)xas.xa_index << PAGE_SHIFT;
-	while ((error = iomap_iter(&iter, ops)) > 0) {
+	while (iomap_iter(&iter, ops) > 0) {
 		if (iomap_length(&iter) < PMD_SIZE)
 			continue; /* actually breaks out of the loop */