Use "e" constraint in place of "i" to match x86_64_general_operand

Use "e" constraint in place of "i" to match x86_64_general_operand

The fix for bug 3549 (commit d913bb7) was incomplete.  When the
x86_64_general_operand predicate is used, the corresponding operand
constraint must be "e" rather than "i".  The predicate controls only
whether the instruction pattern is selected in initial RTL generation.
The constraint controls how operands can be replaced by later phases
of the compiler, such as the "reload" steps done by register allocation.
The "i" constraint accepts a SYMBOL_REF under -fPIC while "e" does not.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3793
TEST= toolchain trybots
R=sehr@chromium.org, khim@chromium.org

Committed: https://git.chromium.org/gitweb?p=native_client/nacl-gcc.git;a=commit;h=093bbb4

[sehr, 2014-02-20 17:28:52]

I'm going to trust you on this one, as the tools don't let me read the patch. 
LGTM.

[Roland McGrath, 2014-02-20 17:32:20]

Committed patchset #1 manually as r093bbb4 (presubmit successful).