x86/fpu: Move fpu__save() to fpu/internals.h

It's an internal method, not a driver API, so move it from fpu/api.h
to fpu/internal.h.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/fpu/api.h

@@ -99,6 +99,4 @@ static inline int user_has_fpu(void)
 	return current->thread.fpu.fpregs_active;
 }
 
-extern void fpu__save(struct fpu *fpu);
-
 #endif /* _ASM_X86_FPU_API_H */

arch/x86/include/asm/fpu/internal.h

@@ -290,6 +290,8 @@ static inline int fpu_save_init(struct fpu *fpu)
 	return 1;
 }
 
+extern void fpu__save(struct fpu *fpu);
+
 static inline int fpu_restore_checking(struct fpu *fpu)
 {
 	if (use_xsave())