KVM: powerpc: remove -I. header search paths

The header search path -I. in kernel Makefiles is very suspicious;
it allows the compiler to search for headers in the top of $(srctree),
where obviously no header file exists.

Commit 46f43c6e ("KVM: powerpc: convert marker probes to event
trace") first added these options, but they are completely useless.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kvm/Makefile

@@ -10,11 +10,6 @@ common-objs-y = $(KVM)/kvm_main.o $(KVM)/eventfd.o
 common-objs-$(CONFIG_KVM_VFIO) += $(KVM)/vfio.o
 common-objs-$(CONFIG_KVM_MMIO) += $(KVM)/coalesced_mmio.o
 
-CFLAGS_e500_mmu.o := -I.
-CFLAGS_e500_mmu_host.o := -I.
-CFLAGS_emulate.o  := -I.
-CFLAGS_emulate_loadstore.o  := -I.
-
 common-objs-y += powerpc.o emulate_loadstore.o
 obj-$(CONFIG_KVM_EXIT_TIMING) += timing.o
 obj-$(CONFIG_KVM_BOOK3S_HANDLER) += book3s_exports.o