Commit 6735b4632def ("Fonts: Support FONT_EXTRA_WORDS macros for built-in
fonts") introduced the following error when building rpc_defconfig (only
this build appears to be affected):

`acorndata_8x8' referenced in section `.text' of arch/arm/boot/compressed/ll_char_wr.o:
defined in discarded section `.data' of arch/arm/boot/compressed/font.o
`acorndata_8x8' referenced in section `.data.rel.ro' of arch/arm/boot/compressed/font.o:
defined in discarded section `.data' of arch/arm/boot/compressed/font.o
make[3]: *** [/scratch/linux/arch/arm/boot/compressed/Makefile:191: arch/arm/boot/compressed/vmlinux] Error 1
make[2]: *** [/scratch/linux/arch/arm/boot/Makefile:61: arch/arm/boot/compressed/vmlinux] Error 2
make[1]: *** [/scratch/linux/arch/arm/Makefile:317: zImage] Error 2

The .data section is discarded at link time. Reinstating acorndata_8x8 as
const ensures it is still available after linking. Do the same for the
other 12 built-in fonts as well, for consistency purposes.

Cc:
Cc: Russell King
Reviewed-by: Greg Kroah-Hartman
Fixes: 6735b4632def ("Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts")
Signed-off-by: Lee Jones
Co-developed-by: Peilin Ye
Signed-off-by: Peilin Ye
Signed-off-by: Daniel Vetter
Link: https://patchwork.freedesktop.org/patch/msgid/20201102183242.2031659-1-yepeilin.cs@gmail.com