Typos on "Upgrading the OpenWrt-Yun image on the Yún" page

[per1234]

https://www.arduino.cc/en/Tutorial/YunSysupgrade

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Change:

sysupgrade image is available for download here.

to:

sysupgrade image is available for download here.

(fix link, the previous one is invalid)

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Change:

or put it in the root folder of a USB memory

to:

or put it in the root folder of a USB flash drive

[kengdahl]

Fixed