MIPS: BCM5xxx: Remove dead init_fpu code

The BMIPS5xxx core_init function contains a call to an init_fpu function
inside an #ifdef whose condition never evaluates true. Remove the dead
code. FPU initialization happens later, primarily when a userland
program attempts to use it.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21018/
Cc: linux-mips@linux-mips.org