Fix libraries being installed to usr/lib64

pkg.info

@@ -1,7 +1,7 @@
 name: plasma-wayland-protocols
 description: Plasma Specific Protocols for Wayland
 version: 1.19.0
-revision: 1
+revision: 2
 url: https://invent.kde.org/libraries/plasma-wayland-protocols
 license: LGPL2.1-or-later
 architecture: any

source.sh

@@ -5,7 +5,7 @@
 # The build function is executed in the source directory
 # This function is used to compile the source code
 build() {
-  cmake -B build -DCMAKE_INSTALL_PREFIX=/usr
+  cmake -B build -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_INSTALL_LIBDIR=lib
   cmake --build build
 }