ramips: pci-rt2880: 6.12: change pcibios_init declaration

Fixes error:
arch/mips/pci/pci-rt2880.c:267:12: error: no previous prototype for 'pcibios_init' [-Werror=missing-prototypes]
  267 | int __init pcibios_init(void)
      |            ^~~~~~~~~~~~
cc1: all warnings being treated as errors
make[8]: *** [scripts/Makefile.build:229: arch/mips/pci/pci-rt2880.o] Error 1
make[7]: *** [scripts/Makefile.build:478: arch/mips/pci] Error 2

Signed-off-by: Mieczyslaw Nalewaj <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/18654
Signed-off-by: Hauke Mehrtens <[email protected]>

target/linux/ramips/patches-6.12/900-pci-rt2880-static-pcibios_init.patch

@@ -0,0 +1,29 @@
+From 6688b218552c6fd3178b40d7d106bf732caec3aa Mon Sep 17 00:00:00 2001
+From: Mieczyslaw Nalewaj <[email protected]>
+Date: Sat, 28 Dec 2024 18:09:17 +0100
+Subject: [PATCH] pci-rt2880: static pcibios_init
+
+Fixes error:
+arch/mips/pci/pci-rt2880.c:267:12: error: no previous prototype for 'pcibios_init' [-Werror=missing-prototypes]
+  267 | int __init pcibios_init(void)
+      |            ^~~~~~~~~~~~
+cc1: all warnings being treated as errors
+make[8]: *** [scripts/Makefile.build:229: arch/mips/pci/pci-rt2880.o] Error 1
+make[7]: *** [scripts/Makefile.build:478: arch/mips/pci] Error 2
+
+Signed-off-by: Mieczyslaw Nalewaj <[email protected]>
+---
+ arch/mips/pci/pci-rt2880.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+--- a/arch/mips/pci/pci-rt2880.c
++++ b/arch/mips/pci/pci-rt2880.c
+@@ -264,7 +264,7 @@ static struct platform_driver rt288x_pci
+ 	},
+ };
+ 
+-int __init pcibios_init(void)
++static int __init pcibios_init(void)
+ {
+ 	int ret = platform_driver_register(&rt288x_pci_driver);
+