x86/cpu/vmware: Use the full form of INL in VMWARE_HYPERCALL, for clang/llvm

LLVM's assembler doesn't accept the short form INL instruction:

  inl (%%dx)

but instead insists on the output register to be explicitly specified.

This was previously fixed for the VMWARE_PORT macro. Fix it also for
the VMWARE_HYPERCALL macro.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: clang-built-linux@googlegroups.com
Fixes: b4dd4f6e36 ("Add a header file for hypercall definitions")
Link: https://lkml.kernel.org/r/20191021172403.3085-2-thomas_os@shipmail.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/vmware.h

@@ -29,7 +29,8 @@
 
 /* The low bandwidth call. The low word of edx is presumed clear. */
 #define VMWARE_HYPERCALL						\
-	ALTERNATIVE_2("movw $" VMWARE_HYPERVISOR_PORT ", %%dx; inl (%%dx)", \
+	ALTERNATIVE_2("movw $" VMWARE_HYPERVISOR_PORT ", %%dx; "	\
+		      "inl (%%dx), %%eax",				\
 		      "vmcall", X86_FEATURE_VMCALL,			\
 		      "vmmcall", X86_FEATURE_VMW_VMMCALL)