sparc32: Move ioremap/iounmap declaration before asm-generic/io.h include

Move the ioremap/iounmap declaration before asm-generic/io.h is
included so that it is visible within it.

Link: https://lore.kernel.org/r/93e2f23cda474a92a4708d4c50c9c359426a2162.1600254147.git.lorenzo.pieralisi@arm.com


Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: "David S. Miller" <davem@davemloft.net>