board/beaglebone/readme.txt: Minor grammar fixes.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

board/beaglebone/readme.txt

@@ -3,7 +3,7 @@ BeagleBone
 Intro
 =====
 To be able to use BeagleBone board with the images generated by
-Buildroot, you have prepare the SDCard.
+Buildroot, you have to prepare the SDCard.
 
 How to build it
 ===============
@@ -33,8 +33,8 @@ After building, you should get a tree like this:
   └── zImage
 
 
-Prepare you SDCard
-==================
+Prepare your SDCard
+===================
 
 You need to prepare first partition in fat32 and marked as bootable,
 and second where you will write rootfs.
@@ -43,7 +43,7 @@ Copy the files to boot partition
 
   $ cp MLO u-boot.img zImage uEnv.txt *.dtb /media/zzzzz
 
-where /media/zzzzz is the mount point
+where /media/zzzzz is the mount point.
 Then you need to write the rootfs image onto SDCard:
 
   # dd if=rootfs.ext2 of=/dev/xxxxx