Update README

README

 This is the source tree of U-Boot, a popular boot loader for embedded devices. U-Boot was developed by DENX Software Engineering (www.denx.de).
 
-This particular version of U-Boot is maintained by Emcraft Systems and supports several Cortex-M3 and Cortex-M4 based MCUs.
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-A complete list of Cortex-M MCUs and boards supported by this version of U-Boot is available at http://www.emcraft.com.
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-If you want to contribute code to this source tree, please email your patches to a2f-linux-support@emcraft.com.
+This particular version of U-Boot was modified by Emcraft Systems and supports several Cortex-M3 and Cortex-M4 based MCUs.
 
+It has some modifications by the Qt Company for supporting booting to RTOS on STM32F7xxx.