Fix typo in ieeeck.f

inifinity -> infinity

Author: Ikko Ashimine

SRC/ieeeck.f

@@ -41,7 +41,7 @@
 *> \param[in] ISPEC
 *> \verbatim
 *>          ISPEC is INTEGER
-*>          Specifies whether to test just for inifinity arithmetic
+*>          Specifies whether to test just for infinity arithmetic
 *>          or whether to test for infinity and NaN arithmetic.
 *>          = 0: Verify infinity arithmetic only.
 *>          = 1: Verify infinity and NaN arithmetic.