Fix platform.h for C compilation

Allow platform.h to be used by POC files

Change-Id: I809749422e12f4c4b2c616ca0994b158f3cd054c
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4251
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

src/system/boot/platform/amiga_m68k/cpu.cpp

@@ -106,7 +106,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 }

src/system/boot/platform/atari_m68k/cpu.cpp

@@ -131,7 +131,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 }

src/system/boot/platform/bios_ia32/cpu.cpp

@@ -72,7 +72,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 	arch_ucode_load(volume);

src/system/boot/platform/efi/cpu.cpp

@@ -48,7 +48,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 	arch_ucode_load(volume);

src/system/boot/platform/next_m68k/cpu.cpp

@@ -87,7 +87,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 }

src/system/boot/platform/openfirmware/cpu.cpp

@@ -7,7 +7,7 @@
 #include <boot/platform.h>
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 }

src/system/boot/platform/riscv/cpu.cpp

@@ -42,7 +42,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 	// we have no ucode

src/system/boot/platform/u-boot/cpu.cpp

@@ -37,7 +37,7 @@ cpu_init()
 }
 
 
-extern "C" void
+void
 platform_load_ucode(BootVolume& volume)
 {
 }