Undo previous patch, caused linker problems on x86_64/linux

rolling back:

Sat Nov 21 16:43:13 EST 2009  Ben.Lippmeier@anu.edu.au
  * Windows DLLs: Tag imported gmp symbols with the package they're from.

    M ./cbits/gmp-wrappers.cmm -20 +20

cbits/gmp-wrappers.cmm

@@ -28,26 +28,26 @@
 #include "Cmm.h"
 #include "GmpDerivedConstants.h"
 
-import "integer-gmp" __gmpz_init;
-import "integer-gmp" __gmpz_add;
-import "integer-gmp" __gmpz_sub;
-import "integer-gmp" __gmpz_mul;
-import "integer-gmp" __gmpz_mul_2exp;
-import "integer-gmp" __gmpz_fdiv_q_2exp;
-import "integer-gmp" __gmpz_gcd;
-import "integer-gmp" __gmpn_gcd_1;
-import "integer-gmp" __gmpn_cmp;
-import "integer-gmp" __gmpz_tdiv_q;
-import "integer-gmp" __gmpz_tdiv_r;
-import "integer-gmp" __gmpz_tdiv_qr;
-import "integer-gmp" __gmpz_fdiv_qr;
-import "integer-gmp" __gmpz_divexact;
-import "integer-gmp" __gmpz_and;
-import "integer-gmp" __gmpz_xor;
-import "integer-gmp" __gmpz_ior;
-import "integer-gmp" __gmpz_com;
-
-import "integer-gmp" integer_cbits_decodeDouble;
+#ifdef __PIC__
+#ifndef mingw32_HOST_OS
+import __gmpz_init;
+import __gmpz_add;
+import __gmpz_sub;
+import __gmpz_mul;
+import __gmpz_gcd;
+import __gmpn_gcd_1;
+import __gmpn_cmp;
+import __gmpz_tdiv_q;
+import __gmpz_tdiv_r;
+import __gmpz_tdiv_qr;
+import __gmpz_fdiv_qr;
+import __gmpz_divexact;
+import __gmpz_and;
+import __gmpz_xor;
+import __gmpz_ior;
+import __gmpz_com;
+#endif
+#endif
 
 /* -----------------------------------------------------------------------------
    Arbitrary-precision Integer operations.