triggerhappy uses pkg-config to detect the systemd library. Make sure it
uses the target pkg-config, not the host one.
Fixes build failure when the host has systemd pkg-config files:
.../host/bin/arm-linux-gcc -static th-cmd.o cmdsocket.o -lsystemd -o th-cmd
.../host/opt/ext-toolchain/bin/../lib/gcc/arm-buildroot-linux-uclibcgnueabi/6.4.0/../../../../arm-buildroot-linux-uclibcgnueabi/bin/ld: cannot find -lsystemd
Cc: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit b4a7145b0b)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
56be42df17