matchbox-desktop: needs zlib

Otherwise the build fails with:

In file included from mbdesktop_win_plugin.c:1:0:
mbdesktop.h:31:18: fatal error: zlib.h: No such file or directory

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
matchbox-wm: fix mbtheme build issue when png support is disabled

Fixes http://autobuild.buildroot.net/results/c02af7b66ae2c14d94edaa940f9edfcde9a9fad5

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Revert "uClibc: port linuxthreads errno patch to 0.9.33.2"

This reverts commit 1d8c3e6caf6be14644ef8ef5ae2704105322442b

The forward port breaks compilation at least for SPARC NPTL toolchains:

LD libuClibc-0.9.33.2.so
libc/libc_so.a(pipe.os): In function `__GI_pipe':
(.text+0x38): undefined reference to `__GI___errno_location'
collect2: ld returned 1 exit status

Easily triggered by a "make qemu_sparc_ss10_defconfig && make".

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>