ipq40xx: fix typo in Linksys WHW01 image definition

Use lower-case "k" in IMAGE_SIZE for Linksys WHW01, permitting proper unit
conversions in build recipes (e.g. 75776k -> 75776*1024).

Fixes: 2a9f3b7717 ("ipq40xx: fix up Linksys WHW01 board name, device definition")
Signed-off-by: Tony Ambardar <[email protected]>

target/linux/ipq40xx/image/generic.mk

@@ -742,7 +742,7 @@ define Device/linksys_whw01
 	DEVICE_VENDOR := Linksys
 	DEVICE_MODEL := WHW01
 	KERNEL_SIZE := 6144k
-	IMAGE_SIZE := 75776K
+	IMAGE_SIZE := 75776k
 	SOC := qcom-ipq4018
 	BLOCKSIZE := 128k
 	PAGESIZE := 2048