The nvdimm test wraps a number of API functions, but these functions
don't have a prototype in a header because they are all called
by a different name:

drivers/nvdimm/../../tools/testing/nvdimm/test/iomap.c:74:15: error: no previous prototype for '__wrap_devm_ioremap' [-Werror=missing-prototypes]
   74 | void __iomem *__wrap_devm_ioremap(struct device *dev,
      |               ^~~~~~~~~~~~~~~~~~~
drivers/nvdimm/../../tools/testing/nvdimm/test/iomap.c:86:7: error: no previous prototype for '__wrap_devm_memremap' [-Werror=missing-prototypes]
   86 | void *__wrap_devm_memremap(struct device *dev, resource_size_t offset,
      |       ^~~~~~~~~~~~~~~~~~~~
...

Add prototypes to avoid the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230516201415.556858-2-arnd@kernel.orgSigned-off-by: Dan Williams <dan.j.williams@intel.com>