math: remove sun copyright from libm.h

Nothing is left from the original fdlibm header nor from the bsd
modifications to it other than some internal api declarations.

Comments are dropped that may be copyrightable content.

src/internal/libm.h

@@ -1,15 +1,3 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/math_private.h */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-
 #ifndef _LIBM_H
 #define _LIBM_H
 
@@ -88,7 +76,6 @@ union ldshape {
 #define asuint64(f) ((union{double _f; uint64_t _i;}){f})._i
 #define asdouble(i) ((union{uint64_t _i; double _f;}){i})._f
 
-/* Get two 32 bit ints from a double.  */
 #define EXTRACT_WORDS(hi,lo,d)                    \
 do {                                              \
   uint64_t __u = asuint64(d);                     \
@@ -96,46 +83,37 @@ do {                                              \
   (lo) = (uint32_t)__u;                           \
 } while (0)
 
-/* Get the more significant 32 bit int from a double.  */
 #define GET_HIGH_WORD(hi,d)                       \
 do {                                              \
   (hi) = asuint64(d) >> 32;                       \
 } while (0)
 
-/* Get the less significant 32 bit int from a double.  */
 #define GET_LOW_WORD(lo,d)                        \
 do {                                              \
   (lo) = (uint32_t)asuint64(d);                   \
 } while (0)
 
-/* Set a double from two 32 bit ints.  */
 #define INSERT_WORDS(d,hi,lo)                     \
 do {                                              \
   (d) = asdouble(((uint64_t)(hi)<<32) | (uint32_t)(lo)); \
 } while (0)
 
-/* Set the more significant 32 bits of a double from an int.  */
 #define SET_HIGH_WORD(d,hi)                       \
   INSERT_WORDS(d, hi, (uint32_t)asuint64(d))
 
-/* Set the less significant 32 bits of a double from an int.  */
 #define SET_LOW_WORD(d,lo)                        \
   INSERT_WORDS(d, asuint64(d)>>32, lo)
 
-/* Get a 32 bit int from a float.  */
 #define GET_FLOAT_WORD(w,d)                       \
 do {                                              \
   (w) = asuint(d);                                \
 } while (0)
 
-/* Set a float from a 32 bit int.  */
 #define SET_FLOAT_WORD(d,w)                       \
 do {                                              \
   (d) = asfloat(w);                               \
 } while (0)
 
-/* fdlibm kernel functions */
-
 hidden int    __rem_pio2_large(double*,double*,int,int,int);
 
 hidden int    __rem_pio2(double,double*);
@@ -155,7 +133,6 @@ hidden long double __sinl(long double, long double, int);
 hidden long double __cosl(long double, long double);
 hidden long double __tanl(long double, long double, int);
 
-/* polynomial evaluation */
 hidden long double __polevll(long double, const long double *, int);
 hidden long double __p1evll(long double, const long double *, int);