luasec: Replace -fPIC with $(FPIC)

Currently i386 and the PPC targets have issues linking issues.

https://github.com/openwrt/packages/issues/3319

says that replacing -fPIC with -fpic works.

Patch added to avoid package overriding settings set by toolchain and make
compilation less noisy

Signed-off-by: Rosen Penev <rosenp@gmail.com>
(cherry-picked from cf23dd2eb0)

lang/luasec/patches/100-fix-compilation.patch

@@ -0,0 +1,13 @@
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -13,8 +13,8 @@ WARN=-Wall -pedantic
+ BSD_CFLAGS=-O2 -fPIC $(WARN) $(INCDIR) $(DEFS)
+ BSD_LDFLAGS=-O -fPIC -shared $(LIBDIR)
+ 
+-LNX_CFLAGS=-O2 -fPIC $(WARN) $(INCDIR) $(DEFS)
+-LNX_LDFLAGS=-O -fPIC -shared $(LIBDIR)
++LNX_CFLAGS=$(INCDIR) $(DEFS)
++LNX_LDFLAGS=-shared $(LIBDIR)
+ 
+ MAC_ENV=env MACOSX_DEPLOYMENT_TARGET='$(MACVER)'
+ MAC_CFLAGS=-O2 -fno-common $(WARN) $(INCDIR) $(DEFS)