pidgin/pidgin

Install our appdata file to $(datadir)/metainfo as that change was made a long time ago

This patch originates from Lars Wendler from Gentoo

https://gitweb.gentoo.org/repo/gentoo.git/commit/net-im/pidgin/files/pidgin-2.13.0-metainfo.patch?id=2dd6c1852251b5b67c3045badf173be9535b97a9

Testing Done:
Installed to a prefix and verified the file ended up in `$prefix/share/metainfo`

Reviewed at https://reviews.imfreedom.org/r/607/
capdir = $(libdir)/pidgin
cap_la_LDFLAGS = -module -avoid-version
if PLUGINS
cappixdir = $(datadir)/pixmaps/pidgin/buttons
cap_LTLIBRARIES = cap.la
cap_la_SOURCES = \
cap.h \
cap.c \
cap_statistics.h
endif
cap_la_LIBADD = $(GTK_LIBS) $(SQLITE3_LIBS)
AM_CPPFLAGS = \
-DDATADIR=\"$(datadir)\" \
-I$(top_srcdir)/libpurple \
-I$(top_builddir)/libpurple \
-I$(top_srcdir)/pidgin \
$(DEBUG_CFLAGS) \
$(GTK_CFLAGS) \
$(SQLITE3_CFLAGS)
EXTRA_DIST = Makefile.mingw