Add build rule for build-octave (bug #49503). * src/build-octave.mk: Add new build rule for build-octave which can be used for cross-building binary packages that depend on Octave as a build tool. * dist-files.mk: Add new file to list. * index.html: Add new package to list. * src/of-communications.mk, src/of-image.mk, src/of-mapping.mk, src/of-optiminterp.mk, src/of-sparsersb.mk, src/of-statistics.mk, src/of-windows.mk: Add optional dependency on build-octave. * configure.ac: Add new configure switch "--disable-system-octave" that is needed to build the build-octave package. * Makefile.in: Add variable "USE_SYSTEM_OCTAVE". Exclude build-octave from the default build tools and build it only if a package explicitly depends on it. Display warning about missing native Octave version only if necessary.

# This file is part of MXE.
# See index.html for further information.

PKG             := librtmp
$(PKG)_IGNORE   :=
$(PKG)_VERSION  := 2.4
$(PKG)_CHECKSUM := b65ce7708ae79adb51d1f43dd0b6d987076d7c42
$(PKG)_SUBDIR   := rtmpdump-2.3
$(PKG)_FILE     := rtmpdump-2.3.tgz
$(PKG)_URL      := http://rtmpdump.mplayerhq.hu/download/$($(PKG)_FILE)
$(PKG)_DEPS     := gnutls

define $(PKG)_UPDATE
    echo 'Warning: Updates are temporarily disabled for package librtmp.' >&2;
    echo $(librtmp_VERSION)
endef

define $(PKG)_BUILD
    $(MAKE) -C '$(1)' \
        CROSS_COMPILE='$(MXE_TOOL_PREFIX)' \
        prefix='$(HOST_PREFIX)' \
        SYS=mingw \
        CRYPTO=GNUTLS \
        SHARED=no \
        -j '$(JOBS)' install
endef