Fix the following build error with binutils 2.25.

  CC      arch/mips/mm/sc-ip22.o
{standard input}: Assembler messages:
{standard input}:132: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:159: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:200: Error: number (0x9000000080000000) larger than 32 bits
scripts/Makefile.build:293: recipe for target 'arch/mips/mm/sc-ip22.o' failed
make[1]: *** [arch/mips/mm/sc-ip22.o] Error 1

MIPS has used .set mips3 to temporarily switch the assembler to 64 bit
mode in 64 bit kernels virtually forever.  Binutils 2.25 broke this
behavious partially by happily accepting 64 bit instructions in .set mips3
mode but puking on 64 bit constants when generating 32 bit ELF.  Binutils
2.26 restored the old behaviour again.

Fix build with binutils 2.25 by open coding the offending

	dli $1, 0x9000000080000000

as

	li	$1, 0x9000
	dsll	$1, $1, 48

which is ugly be the only thing that will build on all binutils vintages.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: stable@vger.kernel.org