Isolation: fixed the generation of mounts table.

Since the introduction of rootfs feature, some language modules
can't be configured multiple times.

Now the configure generates a separate nxt_<module>_mounts.h for
each module compiled.

auto/modules/python

@@ -130,13 +130,13 @@ if grep ^$NXT_PYTHON_MODULE: $NXT_MAKEFILE 2>&1 > /dev/null; then
 fi
 
 
-NXT_PYTHON_MOUNTS_HEADER=$NXT_BUILD_DIR/nxt_python_mounts.h
+NXT_PYTHON_MOUNTS_HEADER=nxt_${NXT_PYTHON_MODULE}_mounts.h
 
 $NXT_PYTHON -c 'import os.path
 import sys
 pyver = "python" + str(sys.version_info[0]) + "." + str(sys.version_info[1])
 
-print("static const nxt_fs_mount_t  nxt_python%d%d_mounts[] = {" % (sys.version_info[0], sys.version_info[1]))
+print("static const nxt_fs_mount_t  nxt_python_mounts[] = {")
 
 pattern = "{(u_char *) \"%s\", (u_char *) \"%s\", (u_char *) \"bind\", NXT_MS_BIND|NXT_MS_REC, NULL},"
 base = None
@@ -157,7 +157,7 @@ for p in sys.path:
 
 print("};\n\n")
 
-' >> $NXT_PYTHON_MOUNTS_HEADER
+' > $NXT_BUILD_DIR/$NXT_PYTHON_MOUNTS_HEADER
 
 
 $echo " + Python module: ${NXT_PYTHON_MODULE}.unit.so"
@@ -185,7 +185,8 @@ for nxt_src in $NXT_PYTHON_MODULE_SRCS; do
     cat << END >> $NXT_MAKEFILE
 
 $NXT_BUILD_DIR/$nxt_obj:	$nxt_src $NXT_VERSION_H
-	\$(CC) -c \$(CFLAGS) \$(NXT_INCS) $NXT_PYTHON_INCLUDE \\
+	\$(CC) -c \$(CFLAGS) -DNXT_PYTHON_MOUNTS_H=\"$NXT_PYTHON_MOUNTS_HEADER\" \\
+           \$(NXT_INCS) $NXT_PYTHON_INCLUDE \\
 	$nxt_dep_flags \\
 	-o $NXT_BUILD_DIR/$nxt_obj $nxt_src
 	$nxt_dep_post