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/java

@@ -227,7 +227,6 @@ NXT_JAVA_INSTALL_JARS=
 NXT_JAVA_UNINSTALL_JARS=
 
 NXT_JAVA_JARS=$NXT_BUILD_DIR/$NXT_JAVA_MODULE/nxt_jars.h
-NXT_JAVA_MOUNTS_HEADER=$NXT_BUILD_DIR/$NXT_JAVA_MODULE/nxt_java_mounts.h
 mkdir -p $NXT_BUILD_DIR/$NXT_JAVA_MODULE
 
 cat << END > $NXT_JAVA_JARS
@@ -318,7 +317,10 @@ NXT_JAVA_LIBC_DIR=`ldd "$NXT_JAVA_LIBJVM" | grep libc.so | cut -d' ' -f3`
 NXT_JAVA_LIBC_DIR=`dirname $NXT_JAVA_LIBC_DIR`
 fi
 
-cat << END > $NXT_JAVA_MOUNTS_HEADER
+
+NXT_JAVA_MOUNTS_HEADER=nxt_${NXT_JAVA_MODULE}_mounts.h
+
+cat << END > $NXT_BUILD_DIR/$NXT_JAVA_MOUNTS_HEADER
 #ifndef _NXT_JAVA_MOUNTS_H_INCLUDED_
 #define _NXT_JAVA_MOUNTS_H_INCLUDED_
 
@@ -371,7 +373,8 @@ for nxt_src in $NXT_JAVA_MODULE_SRCS; do
 
 $NXT_BUILD_DIR/$nxt_obj: $nxt_src $NXT_VERSION_H
 	mkdir -p $NXT_BUILD_DIR/src/java
-	\$(CC) -c \$(CFLAGS) \$(NXT_INCS) $NXT_JAVA_INCLUDE \\
+	\$(CC) -c \$(CFLAGS) -DNXT_JAVA_MOUNTS_H=\"$NXT_JAVA_MOUNTS_HEADER\" \\
+           \$(NXT_INCS) $NXT_JAVA_INCLUDE \\
 	$nxt_dep_flags \\
 	-o $NXT_BUILD_DIR/$nxt_obj $nxt_src
 	$nxt_dep_post