ARM: 9082/1: [v2] mark prepare_page_table as __init

In some configurations when building with gcc-11, prepare_page_table
does not get inline, which causes a build time warning for a section
mismatch:

WARNING: modpost: vmlinux.o(.text.unlikely+0xce8): Section mismatch in reference from the function prepare_page_table() to the (unknown reference) .init.data:(unknown)
The function prepare_page_table() references
the (unknown reference) __initdata (unknown).
This is often because prepare_page_table lacks a __initdata
annotation or the annotation of (unknown) is wrong.

Mark the function as __init to avoid the warning regardless of the
inlining, and remove the 'inline' keyword. The compiler is
free to ignore the 'inline' here and it doesn't result in better
object code or more readable source.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>