package libarchive: enable shared build

src/libarchive.mk

@@ -18,12 +18,11 @@ define $(PKG)_UPDATE
 endef
 
 define $(PKG)_BUILD
-    $(SED) -i '1i#ifndef LIBARCHIVE_STATIC\n#define LIBARCHIVE_STATIC\n#endif' -i '$(1)/libarchive/archive.h'
-    $(SED) -i '1i#ifndef LIBARCHIVE_STATIC\n#define LIBARCHIVE_STATIC\n#endif' -i '$(1)/libarchive/archive_entry.h'
+    $(if $(BUILD_STATIC),\
+        $(SED) -i '1i#ifndef LIBARCHIVE_STATIC\n#define LIBARCHIVE_STATIC\n#endif' -i '$(1)/libarchive/archive.h'
+        $(SED) -i '1i#ifndef LIBARCHIVE_STATIC\n#define LIBARCHIVE_STATIC\n#endif' -i '$(1)/libarchive/archive_entry.h')
     cd '$(1)' && ./configure \
-        --host='$(TARGET)' \
-        --prefix='$(PREFIX)/$(TARGET)' \
-        --disable-shared \
+        $(MXE_CONFIGURE_OPTS) \
         --disable-bsdtar \
         --disable-bsdcpio \
         --disable-bsdcat \
@@ -36,5 +35,3 @@ define $(PKG)_BUILD
         '$(2).c' -o '$(PREFIX)/$(TARGET)/bin/test-libarchive.exe' \
         `'$(TARGET)-pkg-config' --libs-only-l libarchive`
 endef
-
-$(PKG)_BUILD_SHARED =