Fixes#7372
Added patch method which renames config.h in the fftw subdir of the
source tree. fftw 2.1.5 appears to ship with a copy of this file
with all defines commented out. This gets read by the #include
directives instead of the version in the build directory with the
correct defines. As a result, many C preprocessor macros left
undefined, including F77_FUNC_ which causes the bulk of fttwf77.c
to be skipped due to an #ifdef, so fftw_reverse_int_array et al
not included in library. Fixes#7372
Also fixed some inconsistencies with the handling of quad and
long_double in specs between the configure method and the build,
check, and install methods.
c42528fac2