parisc: Avoid build warnings with -Wno-address-of-packed-member compiler option

Add this option to avoid some warnings like:

src/tcgbios.c: In function 'tpm_interrupt_handler32':
src/tcgbios.c:1721:45: warning: taking address of packed member of 'struct bregs' may result
                in an unaligned pointer value [-Waddress-of-packed-member]

Signed-off-by: Helge Deller <deller@gmx.de>
diff --git a/Makefile.parisc b/Makefile.parisc
index 4af49b6..d3278e3 100644
--- a/Makefile.parisc
+++ b/Makefile.parisc
@@ -68,7 +68,7 @@
 CPPFLAGS = -P -MD -MT $@
 
 COMMONCFLAGS := -I$(OUT) -Isrc -Ivgasrc -Os -MD -g \
-    -Wall -Wno-strict-aliasing -Wold-style-definition \
+    -Wall -Wno-strict-aliasing -Wold-style-definition -Wno-address-of-packed-member \
     $(call cc-option,$(CC),-Wtype-limits,) \
     -fomit-frame-pointer \
     -freg-struct-return -ffreestanding -fno-delete-null-pointer-checks \