Force use of -fPIC

--- sqlite-src-3530100/main.mk.orig	2026-05-06 19:21:16.565581458 +0200
+++ sqlite-src-3530100/main.mk	2026-05-06 19:23:02.495612617 +0200
@@ -1679,7 +1679,7 @@
 # $(CFLAGS.tclextension) = CFLAGS for the tclextension* targets.
 #
 CFLAGS.tclextension = $(CFLAGS.intree_includes) $(CFLAGS.env) \
-  $(OPT_FEATURE_FLAGS) $(OPTS) $(CFLAGS.icu)
+  $(OPT_FEATURE_FLAGS) $(OPTS) $(CFLAGS.icu) -fPIC
 #
 # Build the SQLite TCL extension in a way that make it compatible
 # with whatever version of TCL is running as $TCLSH_CMD, possibly defined