Reorder registers in other x86_64 assembler files

This fixes the previous commit which changed the register order in
swapcontext only, which caused setcontext to subtly corrupt the stack.

arch/x86_64/getcontext.S

@@ -22,8 +22,8 @@ __getcontext:
 	movq	%r14, 88(%rdi)
 	movq	%r15, 96(%rdi)
 	movq	%rdi, 104(%rdi)
-	movq	%rbp, 112(%rdi)
-	movq	%rsi, 120(%rdi)
+	movq	%rsi, 112(%rdi)
+	movq	%rbp, 120(%rdi)
 	movq	%rbx, 128(%rdi)
 	movq	%rdx, 136(%rdi)
 	movq	$1, 144(%rdi)		/* $1 is %rax */

arch/x86_64/setcontext.S

@@ -21,8 +21,8 @@ __setcontext:
 	movq    80(%rdi), %r13
 	movq    88(%rdi), %r14
 	movq    96(%rdi), %r15
-	movq    112(%rdi), %rbp
-	movq    120(%rdi), %rsi
+	movq    112(%rdi), %rsi
+	movq    120(%rdi), %rbp
 	movq    128(%rdi), %rbx
 	movq    136(%rdi), %rdx
 	movq    144(%rdi), %rax