tools: Find the NetworkManager-all-sym binary location.
When building NetworkManager with slibtool (https://dev.midipix.org/cross/slibtool) it will compile, but then it will fail to correctly work during runtime. For example it does not find my wifi device.
This is because the create-exports-NetworkManager.sh
script hardcodes the of the build binary.
With slibtool this is instead a libtool wrapper script and not the actual binary.
$ find ./src/ -type f -name NetworkManager-all-sym -exec file {} \;
./src/.libs/NetworkManager-all-sym: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, not stripped
./src/NetworkManager-all-sym: POSIX shell script, ASCII text executable
This MR attempts to automatically find the correct NetworkManager-all-sym
binary without depending on it being in a specific location which is enough to fix NetworkManager when built with slibtool.