efi_loader: simplify logical expression in efi_disk_add_dev()

To check if a variable is non-zero there is no need for '!= 0'.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index 9563556..fc0682b 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -367,7 +367,7 @@
 	diskobj->media.block_size = desc->blksz;
 	diskobj->media.io_align = desc->blksz;
 	diskobj->media.last_block = desc->lba - offset;
-	if (part != 0)
+	if (part)
 		diskobj->media.logical_partition = 1;
 	diskobj->ops.media = &diskobj->media;
 	if (disk)