brcmfmac: make brcmf_fw_nvram_strip() static

The function brcmf_fw_nvram_strip() is no longer called so
it does not need to be exposed.

Reviewed-by: Hante Meuleman <[e-mail]>
Reviewed-by: Franky (Zhenhui) Lin <[e-mail]>
Reviewed-by: Daniel (Deognyoun) Kim <[e-mail]>
Reviewed-by: Pieter-Paul Giesberts <[e-mail]>
Signed-off-by: Arend van Spriel <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

drivers/net/wireless/brcm80211/brcmfmac/firmware.c

···
  * and converts newlines to NULs. Shortens buffer as needed and pads with NULs.
  * End of buffer is completed with token identifying length of buffer.
  */
-void *brcmf_fw_nvram_strip(const struct firmware *nv, u32 *new_length)
+static void *brcmf_fw_nvram_strip(const struct firmware *nv, u32 *new_length)
 {
 	struct nvram_parser nvp;
 	u32 pad;

drivers/net/wireless/brcm80211/brcmfmac/firmware.h

···
 #define BRCMF_FW_REQ_FLAGS		0x00F0
 #define  BRCMF_FW_REQ_NV_OPTIONAL	0x0010
 
-void *brcmf_fw_nvram_strip(const struct firmware *nv, u32 *new_length);
 void brcmf_fw_nvram_free(void *nvram);
 /*
  * Request firmware(s) asynchronously. When the asynchronous request