Old toolchains don't know about slbfee and break the build, eg:
{standard input}:37: Error: Unrecognized opcode: `slbfee.'
Fix it by using the macro version. We need to add an underscore
version that takes raw register numbers from the inline asm, rather
than our Rx macros.
Fixes: e15a4fea4d ("powerpc/64s/hash: Add some SLB debugging tests")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
08e6a3434e