[openwrt/openwrt] base-files: read all 3 bytes in get_magic_vfat() at once

[LEDE Commits]

adrian pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/81655e1450a80276db32c8a8e10de73a256bc664

commit 81655e1450a80276db32c8a8e10de73a256bc664
Author: Adrian Schmutzler <freifunk at adrianschmutzler.de>
AuthorDate: Mon Jan 4 01:28:44 2021 +0100

    base-files: read all 3 bytes in get_magic_vfat() at once
    
    While the speed improvement might be negligible, there is still no
    reason to read individual bytes.
    
    Signed-off-by: Adrian Schmutzler <freifunk at adrianschmutzler.de>
---
 package/base-files/Makefile                    | 2 +-
 package/base-files/files/lib/upgrade/common.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/package/base-files/Makefile b/package/base-files/Makefile
index 8d40eb0e49..f18f221129 100644
--- a/package/base-files/Makefile
+++ b/package/base-files/Makefile
@@ -12,7 +12,7 @@ include $(INCLUDE_DIR)/version.mk
 include $(INCLUDE_DIR)/feeds.mk
 
 PKG_NAME:=base-files
-PKG_RELEASE:=245
+PKG_RELEASE:=246
 PKG_FLAGS:=nonshared
 
 PKG_FILE_DEPENDS:=$(PLATFORM_DIR)/ $(GENERIC_PLATFORM_DIR)/base-files/
diff --git a/package/base-files/files/lib/upgrade/common.sh b/package/base-files/files/lib/upgrade/common.sh
index e8a28f4138..c28bae48a1 100644
--- a/package/base-files/files/lib/upgrade/common.sh
+++ b/package/base-files/files/lib/upgrade/common.sh
@@ -130,7 +130,7 @@ get_magic_gpt() {
 }
 
 get_magic_vfat() {
-	(get_image "$@" | dd bs=1 count=3 skip=54) 2>/dev/null
+	(get_image "$@" | dd bs=3 count=1 skip=18) 2>/dev/null
 }
 
 get_magic_fat32() {