tools/get-libc-dir: Add support for musl

The assumption that libc.so resolves to a library called libc.so* breaks
down on musl-based systems, where libc.so is implemented internally by
the dynamic loader.

$ ldd /bin/bash
	/lib/ld-musl-x86_64.so.1 (0x7fb99fd94000)
	libreadline.so.8 => /lib/libreadline.so.8 (0x7fb99fc59000)
	libtinfo.so.6 => /lib/libtinfo.so.6 (0x7fb99fc21000)
	libc.so => /lib/ld-musl-x86_64.so.1 (0x7fb99fd94000)
	libtinfow.so.6 => /lib/libtinfow.so.6 (0x7fb99fbe9000)

Signed-off-by: Gabi Falk <[email protected]>

Author: gabifalk

tools/get-libc-dir

@@ -5,4 +5,4 @@ libc="$(
 	ldd "$BASH" |
 		sed -n -e 's|[[:space:]]*libc\.so.*[[:space:]]=>[[:space:]]\(/.*\)[[:space:]](0x.*$|\1|p'
 )"
-printf '%s\n' "${libc%/libc.so*}"
+printf '%s\n' "${libc%/*}"