build: drop unsupported PIC compilation

-fPIC is the default for COFF targets. clang complains if you specify
it, so lets drop it.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>

src/x86_64-unknown-uefi.mesoncross.ini

@@ -11,8 +11,7 @@
 #
 #  - We need to disable the red-zone, as must be able to serve timer
 #    interrupts. Similarly, we disable the stack-protector and compile as
-#    free-standing binary. Lastly, UEFI requires applications to be relocatable
-#    so make sure we compile in PIC mode.
+#    free-standing binary.
 #
 #  - UEFI uses UCS-2 strings, so use the 'short-wchar' option to allow use of
 #    wide-string literals in combination with UEFI APIs.
@@ -45,7 +44,6 @@ c_args =
                 '-fno-stack-protector',
                 '-ffreestanding',
                 '-fshort-wchar',
-                '-fpic',
                 '-mno-red-zone',
                 '-mno-mmx',
                 '-mno-sse',