S7D/S6 : fix dynamic bl2ex size [1/1]

PD#SWPL-178900

Problem:
save blob-bl2e/x.bin for device-sign

Solution:
fixed

Verify:
S7D/S6

Change-Id: I18118fb6d9b5c0c775c406ec203f9a0bec574f30
Signed-off-by: wenbo.wang <wenbo.wang@amlogic.com>
diff --git a/s7d/build.sh b/s7d/build.sh
index 90f4b87..0105334 100755
--- a/s7d/build.sh
+++ b/s7d/build.sh
@@ -466,25 +466,25 @@
 		if [ "$CONFIG_BL2E_96K" == "y" ] && [ "$bl2e_sz" -lt "116912" ]; then
 			dd if=/dev/zero of=${bl2e}.max bs=1 count=116912 &> /dev/null
 			dd if=${bl2e} of=${bl2e}.max conv=notrunc &> /dev/null
-			mv ${bl2e}.max ${bl2e}
+			bl2e=${bl2e}.max
 		elif [ "$CONFIG_BL2E_128K" == "y" ] && [ "$bl2e_sz" -lt "149680" ]; then
 			dd if=/dev/zero of=${bl2e}.max bs=1 count=149680 &> /dev/null
 			dd if=${bl2e} of=${bl2e}.max conv=notrunc &> /dev/null
-			mv ${bl2e}.max ${bl2e}
+			bl2e=${bl2e}.max
 		elif [ "$CONFIG_BL2E_256K" == "y" ] && [ "$bl2e_sz" -lt "280752" ]; then
 			dd if=/dev/zero of=${bl2e}.max bs=1 count=280752 &> /dev/null
 			dd if=${bl2e} of=${bl2e}.max conv=notrunc &> /dev/null
-			mv ${bl2e}.max ${bl2e}
+			bl2e=${bl2e}.max
 		elif [ "$CONFIG_BL2E_1024K" == "y" ] && [ "$bl2e_sz" -lt "1067184" ]; then
 			dd if=/dev/zero of=${bl2e}.max bs=1 count=1067184 &> /dev/null
 			dd if=${bl2e} of=${bl2e}.max conv=notrunc &> /dev/null
-			mv ${bl2e}.max ${bl2e}
+			bl2e=${bl2e}.max
 		fi
 
 		if [ "$bl2x_sz" -lt "108720" ]; then
 			dd if=/dev/zero of=${bl2x}.max bs=1 count=108720 &> /dev/null
 			dd if=${bl2x} of=${bl2x}.max conv=notrunc &> /dev/null
-			mv ${bl2x}.max ${bl2x}
+			bl2x=${bl2x}.max
 		fi
 	fi
 	file_info_cfg="${output_images}/aml-payload.cfg"