tools/ci.sh: Clean the correct MPY files when batch compiling.

This commit fixes a small yet harmless issue that occurs when invoking
`ci_native_mpy_modules_build` on a persistent environment, as only X64
MPY files would be removed by the cleaning process.

Now the correct architecture is passed at all times when cleaning before
building a natmod for a particular architecture, forcing a full build of
all files to better simulate the CI environment (where there's no state
persisted between runs for this step).

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

tools/ci.sh

@@ -526,14 +526,14 @@ function ci_native_mpy_modules_build {
     fi
     for natmod in deflate features1 features3 features4 framebuf heapq random re
     do
-        make -C examples/natmod/$natmod clean
+        make -C examples/natmod/$natmod ARCH=$arch clean
         make -C examples/natmod/$natmod ARCH=$arch
     done
 
     # features2 requires soft-float on armv7m, rv32imc, and xtensa.  On armv6m
     # the compiler generates absolute relocations in the object file
     # referencing soft-float functions, which is not supported at the moment.
-    make -C examples/natmod/features2 clean
+    make -C examples/natmod/features2 ARCH=$arch clean
     if [ $arch = "rv32imc" ] || [ $arch = "armv7m" ] || [ $arch = "xtensa" ]; then
         make -C examples/natmod/features2 ARCH=$arch MICROPY_FLOAT_IMPL=float
     elif [ $arch != "armv6m" ]; then
@@ -542,7 +542,7 @@ function ci_native_mpy_modules_build {
 
     # btree requires thread local storage support on rv32imc.
     if [ $arch != "rv32imc" ]; then
-        make -C examples/natmod/btree clean
+        make -C examples/natmod/btree ARCH=$arch clean
         make -C examples/natmod/btree ARCH=$arch
     fi
 }