x86/tdx: Skip saving output regs when SEAMCALL fails with VMFailInvalid

[ Upstream commit 03a423d4 ]

If SEAMCALL fails with VMFailInvalid, the SEAM software (e.g., the TDX
module) won't have chance to set any output register.  Skip saving the
output registers to the structure in this case.

Also, as '.Lno_output_struct' is the very last symbol before RET, rename
it to '.Lout' to make it short.

Opportunistically make the asm directives unindented.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/704088f5b4d72c7e24084f7f15bd1ac5005b7213.1692096753.git.kai.huang%40intel.com


Stable-dep-of: f65aa0ad ("x86/tdx: Dynamically disable SEPT violations from causing #VEs")
Signed-off-by: Sasha Levin <sashal@kernel.org>