Revert "fbcon: Use kzalloc() in fbcon_prepare_logo()"

This reverts commit a6a00d7e.

This commit is redundant, as the root cause that resulted in a false
positive was fixed by commit 27f644dc ("x86: kmsan: use C
versions of memset16/memset32/memset64").

Closes: https://lore.kernel.org/r/CAMuHMdUH4CU9EfoirSxjivg08FDimtstn7hizemzyQzYeq6b6g@mail.gmail.com/


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/bd8b71bb13af21cc48af40349db440f794336d3a.1690535849.git.geert+renesas@glider.be