runtime: fix typo

Fixes #15962

Change-Id: I1949e0787f6c2b1e19b9f9d3af2f712606a6d4cf
Reviewed-on: https://go-review.googlesource.com/23786
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/runtime/asm_386.s

@@ -174,7 +174,7 @@ DATA	bad_proc_msg<>+0x00(SB)/8, $"This pro"
 DATA	bad_proc_msg<>+0x08(SB)/8, $"gram can"
 DATA	bad_proc_msg<>+0x10(SB)/8, $" only be"
 DATA	bad_proc_msg<>+0x18(SB)/8, $" run on "
-DATA	bad_proc_msg<>+0x20(SB)/8, $"processe"
+DATA	bad_proc_msg<>+0x20(SB)/8, $"processo"
 DATA	bad_proc_msg<>+0x28(SB)/8, $"rs with "
 DATA	bad_proc_msg<>+0x30(SB)/8, $"MMX supp"
 DATA	bad_proc_msg<>+0x38(SB)/4, $"ort."