sh: move the ARCH_DMA_MINALIGN definition to asm/cache.h

sh: move the ARCH_DMA_MINALIGN definition to asm/cache.h

The sh architecture defines ARCH_DMA_MINALIGN in asm/page.h.  Move it to
asm/cache.h to allow a generic ARCH_DMA_MINALIGN definition in
linux/cache.h without redefine errors/warnings.

Link: https://lkml.kernel.org/r/20230613155245.1228274-4-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>