x86/fpu: Simplify copy_kernel_to_xregs_booting()

copy_kernel_to_xregs_booting() has a second parameter that is the mask
of xfeatures that should be copied - but this parameter is always -1.

Simplify the call site of this function, this also makes it more
similar to the function call signature of other copy_kernel_to*regs()
functions.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
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: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/fpu/xstate.c

@@ -281,7 +281,7 @@ static void __init setup_init_fpu_buf(void)
 	/*
 	 * Init all the features state with header_bv being 0x0
 	 */
-	copy_kernel_to_xregs_booting(&init_fpstate.xsave, -1);
+	copy_kernel_to_xregs_booting(&init_fpstate.xsave);
 
 	/*
 	 * Dump the init state again. This is to identify the init state