Fix a problem where a semantic error confused error recovery to the point

where the parser emitted bogus diagnostics.  Before, when compiling:

  struct A { int X; } someA;

  int func(int, struct A);

  int test1(void *P, int C) {
    return func(((C*40) + *P) / 42+P, someA);
  }

we emitted:

bug3.c:7:25: error: invalid operands to binary expression ('int' and 'void')
    return func(((C*40) + *P) / 42+P, someA);
                 ~~~~~~ ^ ~~
bug3.c:7:31: error: expected ')'
    return func(((C*40) + *P) / 42+P, someA);
                              ^
bug3.c:7:16: error: to match this '('
    return func(((C*40) + *P) / 42+P, someA);
               ^

now we only emit the first.

llvm-svn: 39474