firmware: fix build errors in paged buffer handling code

fw_{grow,map}_paged_buf() need to be defined as static inline
when CONFIG_FW_LOADER_PAGED_BUF is not enabled,
infact fw_free_paged_buf() is also defined as static inline
when CONFIG_FW_LOADER_PAGED_BUF is not enabled.

Fixes the following mutiple definition building errors for Android kernel:

drivers/base/firmware_loader/fallback_efi.o: In function `fw_grow_paged_buf':
fallback_efi.c:(.text+0x0): multiple definition of `fw_grow_paged_buf'
drivers/base/firmware_loader/main.o:(.text+0x73b): first defined here
drivers/base/firmware_loader/fallback_efi.o: In function `fw_map_paged_buf':
fallback_efi.c:(.text+0xf): multiple definition of `fw_map_paged_buf'
drivers/base/firmware_loader/main.o:(.text+0x74a): first defined here

[ slightly corrected the patch description -- tiwai ]

Fixes: 5342e7093f ("firmware: Factor out the paged buffer handling code")
Fixes: 82fd7a8142 ("firmware: Add support for loading compressed files")
Signed-off-by: Mauro Rossi <issor.oruam@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20190722055536.15342-1-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/firmware_loader/firmware.h

@@ -141,8 +141,8 @@ int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed);
 int fw_map_paged_buf(struct fw_priv *fw_priv);
 #else
 static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {}
-int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; }
-int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; }
+static int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; }
+static int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; }
 #endif
 
 #endif /* __FIRMWARE_LOADER_H */