MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select

MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select

MIPS selects HAVE_SYSCALL_TRACEPOINTS twice. The first was added back in
v3.13 by commit 2d7bf993e073 ("MIPS: ftrace: Add support for syscall
tracepoints."), but then a second redundant one was added in v4.2 by
commit fb59e394c30c ("MIPS: ftrace: Enable support for syscall
tracepoints.").

Drop the duplicate select.

Fixes: fb59e394c30c ("MIPS: ftrace: Enable support for syscall tracepoints.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16654/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>