ci: fix pkg-config paths for cross targets

- Add target-specific pkg-config paths for armv7 and aarch64
- Use correct system paths instead of matrix.target interpolation
- Reuse PKG_PATH variable to avoid duplication

.github/workflows/ci.yml

@@ -113,8 +113,13 @@ jobs:
             cargo build --release --target ${{ matrix.target }}
           else
             # Cross compilation requires special paths
-            PKG_CONFIG_PATH="/usr/lib/${{ matrix.target }}/pkgconfig" \
+            if [ "${{ matrix.target }}" = "armv7-unknown-linux-gnueabihf" ]; then
+              PKG_PATH="/usr/lib/arm-linux-gnueabihf/pkgconfig"
+            elif [ "${{ matrix.target }}" = "aarch64-unknown-linux-gnu" ]; then
+              PKG_PATH="/usr/lib/aarch64-linux-gnu/pkgconfig"
+            fi
+            PKG_CONFIG_PATH="$PKG_PATH" \
             PKG_CONFIG_SYSROOT_DIR="/usr" \
-            PKG_CONFIG_LIBDIR="/usr/lib/${{ matrix.target }}/pkgconfig" \
+            PKG_CONFIG_LIBDIR="$PKG_PATH" \
             cross build --release --target ${{ matrix.target }}
           fi