lx_emul: add page macros to x86 shadow headers

* Add page_to_phys and dummy macro for pgprot_device

Original commit provided by Josef Soentgen

Ref genodelabs/genode#4438

repos/dde_linux/src/include/lx_emul/shadow/linux/pgtable.h

@@ -23,6 +23,10 @@ int    pmd_swp_soft_dirty(pmd_t pmd);
 
 void __init pgtable_cache_init(void);
 
+#ifndef pgprot_device
+#define pgprot_device(prot)  (prot)
+#endif
+
 #ifndef pgprot_decrypted
 #define pgprot_decrypted(prot) (prot)
 #endif

repos/dde_linux/src/include/spec/x86/lx_emul/shadow/asm/io.h

@@ -14,6 +14,10 @@
 
 #include <lx_emul/io_port.h>
 
+#ifndef page_to_phys
+#define page_to_phys(page)  ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
+#endif
+
 void __iomem *ioremap(resource_size_t offset, unsigned long size);
 void iounmap(volatile void __iomem *addr);