arm64: fix pmem interface definition

Defining the two functions as 'static inline' and exporting them
leads to the interesting case where we can use the interface
from loadable modules, but not from built-in drivers, as shown
in this link failure:

vers/nvdimm/claim.o: In function `nsio_rw_bytes':
claim.c:(.text+0x1b8): undefined reference to `arch_invalidate_pmem'
drivers/nvdimm/pmem.o: In function `pmem_dax_flush':
pmem.c:(.text+0x11c): undefined reference to `arch_wb_cache_pmem'
drivers/nvdimm/pmem.o: In function `pmem_make_request':
pmem.c:(.text+0x5a4): undefined reference to `arch_invalidate_pmem'
pmem.c:(.text+0x650): undefined reference to `arch_invalidate_pmem'
pmem.c:(.text+0x6d4): undefined reference to `arch_invalidate_pmem'

This removes the bogus 'static inline'.

Fixes: d50e071f ("arm64: Implement pmem API support")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/mm/flush.c

@@ -85,7 +85,7 @@ EXPORT_SYMBOL(flush_dcache_page);
 EXPORT_SYMBOL(flush_icache_range);
 
 #ifdef CONFIG_ARCH_HAS_PMEM_API
-static inline void arch_wb_cache_pmem(void *addr, size_t size)
+void arch_wb_cache_pmem(void *addr, size_t size)
 {
 	/* Ensure order against any prior non-cacheable writes */
 	dmb(osh);
@@ -93,7 +93,7 @@ static inline void arch_wb_cache_pmem(void *addr, size_t size)
 }
 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
 
-static inline void arch_invalidate_pmem(void *addr, size_t size)
+void arch_invalidate_pmem(void *addr, size_t size)
 {
 	__inval_dcache_area(addr, size);
 }