[PATCH 01/19] powerpc: Don't disable kernel FP/VMX/VSX MSR bits on context switch

Writing the MSR is slow, so we want to avoid it whenever possible. A subsequent patch will add a debug option that strictly manages the FP/VMX/VSX unavailable bits. For now just remove it, matching what we do in other areas of the kernel (eg enable_kernel_altivec()). A context switch microbenchma

[PATCH 01/19] powerpc: Don't disable kernel FP/VMX/VSX MSR bits on context switch

Writing the MSR is slow, so we want to avoid it whenever possible. A subsequent patch will add a debug option that strictly manages the FP/VMX/VSX unavailable bits. For now just remove it, matching what we do in other areas of the kernel (eg enable_kernel_altivec()). A context switch microbenchma