pkgconfig: fix parsing mid-line comments (#14920)

vlib/v/pkgconfig/pkgconfig.v

@@ -70,7 +70,7 @@ fn (mut pc PkgConfig) parse_list(s string) []string {
 }
 
 fn (mut pc PkgConfig) parse_line(s string) string {
-	mut r := s.trim_space()
+	mut r := s.split('#')[0]
 	for r.contains('\${') {
 		tok0 := r.index('\${') or { break }
 		mut tok1 := r[tok0..].index('}') or { break }

vlib/v/pkgconfig/test_samples/hogweed.pc

@@ -0,0 +1,19 @@
+prefix=/usr
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+# Uses Requires.private and Libs.private, under the assumption that
+# when using shared libraries, the ELF dependencies from libhogweed.so
+# to nettle and gmp work.
+
+Name: Hogweed
+Description: Nettle low-level cryptographic library (public-key algorithms)
+URL: http://www.lysator.liu.se/~nisse/nettle
+Version: 3.8
+Requires: # nettle
+Requires.private:  nettle
+Libs: -L${libdir} -lhogweed # -lgmp 
+Libs.private:  -lgmp 
+Cflags: -I${includedir}
+

vlib/v/pkgconfig/test_samples/nettle.pc

@@ -0,0 +1,11 @@
+prefix=/usr
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: Nettle
+Description: Nettle low-level cryptographic library (symmetric algorithms)
+URL: http://www.lysator.liu.se/~nisse/nettle
+Version: 3.8
+Libs: -L${libdir} -lnettle
+Cflags: -I${includedir}