Fixed a few warnings. Rev: src/global.h:1.71 Rev: src/module_support.h:1.12 Rev: src/modules/Gmp/mpf.cmod:1.8 Rev: src/modules/Gmp/mpq.cmod:1.9 Rev: src/modules/HTTPLoop/requestobject.c:1.20 Rev: src/modules/Image/encodings/xcf.c:1.40 Rev: src/modules/Image/layers.c:1.78 Rev: src/modules/Math/math_module.h:1.7 Rev: src/modules/Math/transforms.cmod:1.5 Rev: src/modules/Parser/html.c:1.151 Rev: src/modules/_Charset/charsetmod.c:1.34 Rev: src/modules/_Crypto/include/crypto_types.h:1.6 Rev: src/pike_threadlib.h:1.15