Fix missing type encoding case for long double.
This was triggered when upgrading ivars from the pre-2.0 ABI that used
long double - their alignment could not be calculated correctly and we
hit an assertion.
Fixes:
#ifndef APPLY_TYPE
#error Define APPLY_TYPE(type, name, capitalizedName, encodingChar) before including this file
#endif
+APPLY_TYPE(long double, long double, LongDouble, 'D')
APPLY_TYPE(double, double, Double, 'd')
APPLY_TYPE(float, float, Float, 'f')
APPLY_TYPE(signed char, char, Char, 'c')
