Add missing fcio function to llvm-mos build (#56)

The commodore targets on llvm-mos has gained stdio
support which now enables the missing features in
fcio. Note though that the llvm-mos stdio is largely
untested on mega65 and things might not work. This
should eventually be fixed but in llvm-mos, not in
mega65-libc.

src/fcio.c

@@ -105,9 +105,6 @@ int gBottomBorder;
 bool csrflag; // cursor on/off
 bool autoCR;
 
-#ifdef __clang__
-#pragma GCC warning "readExt() is not implemented for clang yet"
-#else
 unsigned int readExt(FILE* inFile, himemPtr addr, byte skipCBMAddressBytes)
 {
 
@@ -133,11 +130,7 @@ unsigned int readExt(FILE* inFile, himemPtr addr, byte skipCBMAddressBytes)
 
     return overallRead;
 }
-#endif
 
-#ifdef __clang__
-#pragma GCC warning "loadExt() is not implemented for clang yet"
-#else
 unsigned int loadExt(char* filename, himemPtr addr, byte skipCBMAddressBytes)
 {
 
@@ -154,7 +147,6 @@ unsigned int loadExt(char* filename, himemPtr addr, byte skipCBMAddressBytes)
 
     return readBytes;
 }
-#endif
 
 void fc_loadReservedBitmap(char* name)
 {
@@ -510,9 +502,6 @@ void fc_addGraphicsRect(
     }
 }
 
-#ifdef __clang__
-#pragma GCC warning "fc_loadFCI() is not implemented for clang yet"
-#else
 fciInfo* fc_loadFCI(char* filename, himemPtr address, himemPtr paletteAddress)
 {
     static byte numColumns, numRows, lastColourIndex;
@@ -598,7 +587,6 @@ fciInfo* fc_loadFCI(char* filename, himemPtr address, himemPtr paletteAddress)
 
     return info;
 }
-#endif
 
 void fc_zeroPalette(byte reservedSysPalette)
 {
@@ -961,9 +949,6 @@ char fc_getkey(void)
     return fc_cgetc();
 }
 
-#ifdef __clang__
-#pragma GCC warning "fc_getnum() is not implemented for clang yet"
-#else
 int fc_getnum(byte maxlen)
 {
     int res;
@@ -973,7 +958,6 @@ int fc_getnum(byte maxlen)
     free(inptr);
     return res;
 }
-#endif
 
 char* fc_input(byte maxlen)
 {