bootloaders: remove old "video=vesa:ywrap,mtrr" kernel param, as done in d-i
d-i removed this in commit 0917b2dde3ff73a204d27dd2f2fffc8a41175ddd
Note: There was inconsistency between grub and syslinux in use of this, with syslinux not having it on graphical rescue and auto modes while grub entries did. The patch to fix that has been dropped since we're removing it everywhere anyway.
(#395040)
Gbp-Dch: Short