fix: add target-specific CFLAGS for cross-compilation

- Add CFLAGS_aarch64_unknown_linux_gnu for manylinux aarch64 builds
- Add CFLAGS_armv7_unknown_linux_gnueabihf for manylinux armv7 builds
- Add CFLAGS_aarch64_unknown_linux_musl for musllinux aarch64 builds
- Add CFLAGS_armv7_unknown_linux_musleabihf for musllinux armv7 builds

The generic CFLAGS was not being passed to the cross-compiler in the
Docker container. Using target-specific environment variables ensures
the flags are properly applied during cross-compilation.

Author: AndPuQing

.github/workflows/pypi.yml

@@ -39,6 +39,8 @@ jobs:
                   manylinux: auto
               env:
                   CFLAGS: "-Wno-error"
+                  CFLAGS_aarch64_unknown_linux_gnu: "-Wno-error"
+                  CFLAGS_armv7_unknown_linux_gnueabihf: "-Wno-error"
             - name: Upload wheels
               uses: actions/upload-artifact@v6
               with:
@@ -70,6 +72,8 @@ jobs:
                   manylinux: musllinux_1_2
               env:
                   CFLAGS: "-Wno-error"
+                  CFLAGS_aarch64_unknown_linux_musl: "-Wno-error"
+                  CFLAGS_armv7_unknown_linux_musleabihf: "-Wno-error"
             - name: Upload wheels
               uses: actions/upload-artifact@v6
               with: